lecture preflight 10
1: Student 1 because the electrons have two path choices. One half of the electrons will take one side of the parallel circuit and the other half will take the other side.
2: AC means alternating current because the current flow alternates between positive and negative directions while DC, or direct current, does not change direction. AC electricity can travel farther distances before losing power, therefore being more efficent than DC.
3: I better understand the difference between amps and voltage. I did not have a clue before!
4: Why do ice cubes stick to your skin when you first take them out of the freezer?
lecture preflight 10
1: I agree with Student 2 because they have the correct reasoning for the amount of current flowing through the circut. Because circut B is a parallel circut, there needs to be more current to get each bulb to light as bright as the one bulb in circut A.
2: AC=alternating current and DC=direct current Alternating current, as its name suggests, is an electrical current that changes direction while direct current is a constant flow of electrons in a single direction.
3: The graphite/carbon inside of pencils is a good conductor of electricity.
4: How can the weather change from HOT to COLD so quickly?
lecture preflight 10
1: I don't agree with either. All three bulbs will have the same brightness. The parallel circuit makes it so each bulb is the same brightness, when compared to A.
2: AC electricity is alternating current, and it can reach a farther distance from one spot. DC electricty is direct current, and cannot reach as far for people/things to use. DC was used for a long time before AC.
3: That connecting a wire to the positive and negative of a battery without a bulb, you will short circuit it.
4: Once a car comes to a stop, why do they make it so you have to keep your foot on the brake? Like why doesn't it just stop until you press the gas again?
lecture preflight 10
1: i agree with student two. Circuit B allows two different paths, since each bulb is more resistant than the wire, two paths is better than one.
2: AC is alternating current and DC is direct current. Direct, the current moves in only one direction and is a much lower voltage than AC. Batteries use DC. AC goes in alternating directions and is used in most everyday things like the electricity from the wall.
3: that is you mix in salt to water it can conduct electricity.
4: if water without salt or other things in it is not that good of a conductor than why is it so dangerous to have electrical appliances fall in the water.
lecture preflight 10
1: Neither. The current will always be the same across the circuit, no matter how the circuit is contstructed. Also, the current between the two lightbulbs in part B is the same because the circuit is set up in parallet. The three lightbulbs will have the same brightness.
2: A/C: Alternating Current D/C: Direct Current
3: You can use steel wool and a battery to light the steel wool on fire.
4: What's the difference between a flourescent light and a conventional light bulb?
lecture preflight 10
1: I agree with student 1's agrument. I believe that the flow will be more in circuit B than circuit A since it is hooked up to two bulbs. The brightness will be equal.
2: n DC, the electrons flow steadily in a single direction, forward. In AC, electrons keep switching directions, sometimes going forwards and then going backwards.
3: That baking soda is a conductor.
4: How does a flash on a camera work?
lecture preflight 10
1: Student 2-- there are twice as many circuits, so there is twice as much flowing from the battery.
2: AC = Alternating Current: direction of current switches many times (50-60) per second and is used in home appliances most often; DC = Direct Current: direction doesn't change; not as useful; harder to generate I don't really see why DC exists-- AC seems so much more useful!
3: Baking soda conducts electricity! Whodda thunk?
4: Why does D/C exist?!?
lecture preflight 10
1: I agree with student 1, because we know that the battery is giving off the same amount of current in each cases, and that current does not increase as it moves through the bulbs. Although the current is divided between the two bulbs, they still have the same brightness as in circuit A because it is set up as a parallel circuit.
2: D/C refers to the direct current which comes from the batteries. A/C refers to the alternating current which comes out of the plugs in the walls and is produced in power stations. A/C is much more powerful than D/C.
3: I thought it was very interesting how parallel circuits produced the same amount of brightness as the single-bulb circuits.
4: What happens when your body burns calories?
lecture preflight 10
1: 2 because the bulbs will be about the same brightness but there is more current through B.
2: AC means alternating current and DC is direct Current. in a circuit the current flows in one direction for DC and it changes direction in AC.
3: how to make fire with a battery and steel wool
4: how do electric guitars work?
lecture preflight 10
1: Students 2 has the right idea.
2: One is more intense? None of my friends knew.
3: parallel circuits have the same brightness as single circuits.
4: How do seasons work?
lecture preflight 10
1: I agree with student 1. As I saw in this week's lab, the current flows through circuit A and makes it extremely bright. However,in the 2nd diagram, the current is divided between two bulbs, making the brightness of those two bulbs less bright than the bulb in diagram A.
2: According to PBS.org, in 1887, DC electricity was king. But becasue of DC electricity's limitations, power plans could only send DC electgricity about a mile before the electricity began to lose power. But then a system based on high-voltage alternatingt current was introduced, which could carry electricity hundreds of miles with little loss of power.
3: Salt and baking soda in water can generate electricty. Very cool!
4: When they have statistics like, "50 million people watched that episode of tv last night", how do they know that?
lecture preflight 10
1: I agree with student 1. I think that the current through the battery in each circuit is the same and it is divided between the two bulbs. This is a parallel circuit. Unlike a series circuit, the current is the same through both bulbs and the resistance is less than in a series circuit. I disagree with student 2 when he or she says that the flow through the battery in circuit B is more than that through the battery in circuit A.
2: Nobody I asked knew what the difference was, however, wisegeek.com said that AC DC has to do with the way electrons flow. He says, "In DC, the electrons flow steadily in a single direction, or "forward." In AC, electrons keep switching directions, sometimes going "forwards" and then going "backwards." The power that comes from our wall outlets is AC, the more common, efficient kind." (www.wisegeek.com)
3: I learned about resistance in relation to currents, I learned how to make a complete closed circuit with a battery, small lightbulb, and a wire, and I learned how to slightly burn steel wool with an electric current.
4: What are the components of fire? Why do people sometimes try and argue that it's alive?
lecture preflight 10
1: I agree with student 2. Because the set up is a parallel circuit so both bulbs are recieving the same amount of electric current so they both have the same brightness.
2: AC stands for alternating current, meaning the current flows in one direction and then the other, continually changing directions. Also an AC voltage is continually chaning between positive and negative. DC stands for direct current, meaning that the current always flows in the same direction but it may increase or decrease. A DC voltage is always positive.
3: That plain bath water is not a good conductor of electricity.
4: Why do they always put those labels on things like hairdryers if water does not conduct electricity well on its on.
lecture preflight 10
1: I agree with neither because student 1 is wrong because the bulbs B are going to be just as bring in A and with student 2, each battery has the same voltage so the same electric current running through the circuit.
2: AC electricty is alternating electricity, the type found in homes and businesses, because it alternates its direction. DC electricty is direct electricty because it is continuous in one direction. Also, AC power can be easily converted from one voltage to another.
3: I learned why it is dangerous to have electricty appliances running by the bathtub and also why you have to get out of the pool when lightening is seen in the distance.
4: Is it possible to become resistance to being electrocuted?
lecture preflight 10
1: Student 1 because there is more resistance in B and thus the current is smaller
2: d/c current flows in one way but ac current has alternating current.
3: The battery bulb setup
4: how do generators work?
lecture preflight 10
1: Student 1 because the circuit is a parallel circuit which means that the current is split between the two bulbs thus creating the bulbs to be slightly more dull.
2: A/C stands for alternating current and D/C stands for direct current. A thermal imaging system that is A/C-coupled has a signal that is centered around the “local average temperature” without an offset or pedestal. This occurs independently across the array. Because of this it only has to deal with the smaller A/C signal and it therefore has the capability of handling substantially greater temperature variations in the scene. If the scene never changes, there is no A/C component to the signal. Therefore A/C-coupled systems employ a chopper. Additionally, most A/C-coupled systems do not calculate temperature from the pixels of the sensor. TICs that use A/C-coupled sensors and have temperature measurement use a fixed, separate pyrometer. A thermal imaging system that is D/C-Coupled must handle the relatively very large offset as well as the signal of interest. This complicates the system because the offsets differ from pixel to pixel, and they vary slowly with time increasing spatial noise in the system. Because of this, DC-Coupled systems must employ a shutter to periodically re-calibrate the scene and minimize Spatial Noise. TICs that use D/C-coupled sensors can have “through the lens” temperature measurement directly from the pixels of the sensor.
3: That working with circuits is a lot of fun because you can experiment with the brightness/dullness of bulbs.
4: How do people know which chicken eggs will be fertilized eggs or which eggs will be sent out to the grocery stores?
lecture preflight 10
1: I agree with student 2. Both light bulbs would be about the same intensity and therefore there must be more current through circuit B. Circuit B would be empty before A would.
2: AC is alternative current meaning it will adjust current accordingly whereas DC is direct current and will not.
3: The current will change due to the difference in the design of the circuit.
4: Why do people breathe into paper bags when they feel nautious?
lecture preflight 10
1: Student 2, In class the bulbs had the same brightness.
2: AC means Alternating current, and DC means Direct current. AC carries a current longer, and DC carries a current shorter lengths and is used in batteries.
3: That a wire gets hot if you attach it to both sides of a battery.
4: How do generators work?
lecture preflight 10
1: I don't agree with either student because the first student is saying that each bulb has half the current and student 2 is saying that the flow through the battery in circuit B is more than that through the battery in circuit A and in reality they have the same amount of current going through both the circuits.
2: I asked my roommate and she said that A/C stands for "accelerated current" and D/C is "deterred current" which means... fast and slow.
3: I learned that pencil lead can actually be a conductor.
4: Why do batteries leak?
lecture preflight 10
1: I agree with neither. The brightness of the bulbs in circuit B is the same as the one bulb in circuit A. Also the same amount of current is going through both circuits, the amount of flow is the same.
2: A/C electricity is alternating current while D/C electricity is direct current.
3: Gas is the solution through which the current is passed.
4: What is the difference between a close and open circuit?
lecture preflight 10
1: Student 2. Even though the brightness is the same, the battery is working twice as hard to create the current (because it has to light two bulbs) so it'll burn out in half the time that Battery A will.
2: Alternating current (A/C) electricity is more high-voltage power that can "carry electricity hundreds of miles with little loss of power" (pbs.org website). Direct current (D/C) electricity loses power easily.
3: I learned about resistence in electric currents--interesting!
4: What is sodium laurel sulfate? I think I saw the sign at my dentist's office.
lecture preflight 10
1: I agree with student 2. We learned that in parallel circuits the same voltage is running through each of the bulbs, and is equal to the voltage coming from the battery. Current is voltage over resistance. The resistance and voltage are the same for both circuits, which means they both have the same current runing through them.
2: They stand for alternating current and direct current. DC current is either always positve or always negative, and AC is both positive and negative. The difference in the direction of flow is that AC flows one way and then the other, continually changing direction, and DC flows in one direction.
3: I learned that parallel circuits provide the same amount of light to each lightbulb.
4: What do the electrolytes in Gatorade do?
lecture preflight 10
1: Student 2 is correct. The current is the same within circuit A and B. However, in circuit B the current flow will be twice as much because of the two bulbs, using more power, but they will be equally as bright.
2: D/C is the direct current and A/C is the alternating current.
3: I=V/R
4: How do video games work?
lecture preflight 10
1: neither. the amount od current is equal in ALL bulbs.
2: those are alternating and direct current. direct always flows from neg to pos, while ac alternates directions
3: batteries can burn that silver metal stuff! fun fun :)
4: how is it that you can hook a battery up to a garage door opener (the little dial pad to punch in a code) and it can open the garage?
lecture preflight 10
1: Student 1. Student 2 is wrong because the current of both circuits are the same.
2: D/C is direct current and A/C is alternating current. D/C outputs a constant voltage, while A/C output fluctuates between positive and negative voltage.
3: Parallel circuits use the same amount of voltage.
4: Nothing
lecture preflight 10
1: I don't really agree with either... both bulbs have the same amount of current flowing through them, but this isn't necessarily explained by the fact that the bulbs are all the same brightness.
2: D/C stands for direct current and comes from batteries. A/C stands for alternating current and comes from plugs in the wall; it is produced in power stations.
3: I learned that there is really only 1 way to build a simple circuit (2 if you count that you can attach the light bulb to either side).
4: Are the rays in a tanning bed the same as the ones really produced by the sun?
lecture preflight 10
1: I believe student 2 except their last statement (flow through battery in circuit B is more than that through the battery in circuit A. I believe they are the same.
2: A/C stands for alternating current and D/C stands for direct current. A thermal imaging system that is A/C-coupled has a signal that is centered around the “local average temperature” without an offset or pedestal. This occurs independently across the array. Because of this it only has to deal with the smaller A/C signal and it therefore has the capability of handling substantially greater temperature variations in the scene. If the scene never changes, there is no A/C component to the signal. Therefore A/C-coupled systems employ a chopper. Additionally, most A/C-coupled systems do not calculate temperature from the pixels of the sensor. TICs that use A/C-coupled sensors and have temperature measurement use a fixed, separate pyrometer. A thermal imaging system that is D/C-Coupled must handle the relatively very large offset as well as the signal of interest. This complicates the system because the offsets differ from pixel to pixel, and they vary slowly with time increasing spatial noise in the system. Because of this, DC-Coupled systems must employ a shutter to periodically re-calibrate the scene and minimize Spatial Noise. TICs that use D/C-coupled sensors can have “through the lens” temperature measurement directly from the pixels of the sensor
3: What a parallel circuit was.
4: How many layers of skin do I have and does everyone have the same amount of layers?
lecture preflight 10
1: 2, V=IR. Since the voltage of the batteries are the same, you have to look at the resistance to find the current. If the resistance goes up, then the current goes down. In circuit B, the resistance goes down, so the current goes up.
2: DC is direct current and the electrons flow continuously. AC is alternating current and the electrons repeatedly switch which direction they are moving in.
3: Pure H2O does not conduct electricity.
4: How is lightning formed?
lecture preflight 10
1: Student 2 is correct because there are more passage ways for current for the circut B, therefore there is more flow of energy.
2: ac=alternating current dc= direct current DC=electrons flow steadily in a single direction "forward" AC=electrons keep switching directions, sometimes "forwards" and then "backwards" AC is more common and effiecient.
3: salt water conducts electricity, but distilled water does not...
4: How does soap break surface tension?
lecture preflight 10
1: I don't agree with either student. First of all, the last comment from each student completely contradicts what they began to talk about. Secondly, the current through these two circuits are not the same. Curcuit B's flow is greater than Curcuit A's because there are 2 routes of flow. The flow in curcuit B begins two times greater because it needs to divide equally into the two light bulbs it passes through.
2: d/c is "direct current" (steady voltage) and a/c is "alternating current" (voltage goes first positive then negative)
3: The different flows of energy within a curcuit. I had no idea how/why electricity works-- it has been so long. Learning about how/why an light bulb shines brighter than others was very interesting too.
4: If you stick your finger in an outlet, you get electricuted..why is this so? Does it have something to do with the energy flow?
lecture preflight 10
1: I believe that student 1 has a good arguement because whenever there is more than one bulb, half the current is directed toward each outlet. Thus, the light emitted from the bulb wuld be less bright for both of them.
2: A/C stands for an alternating current, and D/C stands for a direct current. A/C's magnetic property of current is induction. In a D/C current a magnetic field builds up.
3: I learned that the heat inside a lightbulb is just as hot as the sun. Additionally, I learned that the oxygen inside light bulbs is taken out in order to stop chain reaction.
4: I was wondering what substance exactly is used in the filiment for a light bulb to make it light up so brightly?
lecture preflight 10
1: I agree with student 1. Student 2 is wrong because the brightness in the bulbs is equal because of equal voltage drop, and not because of the same current. In circuit A all of the current goes through the one bulb, while in circuit B the current is divided between the two bulbs.
2: A/C, standing for alternating current, is when the direction of the current changes directions quickly while in D/C the current is continuous.
3: An increase in resistance creates a decrease in current
4: How does a rechargable batter work?
lecture preflight 10
1: I agree with student two because a parallel circuit, which is the circuit shown in picture B, sprads the electrical current out evenly. It is not cut in half even though there are two bulbs attached to it.
2: AC (Alternating Current Electricity), is typically used n homes and businesses. The current alternates direction and the voltage can be changed readily. DC (Direct Current Electricity), is continuous in one direction. It typically flows from a wire and would not be used in homes.
3: I learned that steel wool can spark and eventually start a fire when it is placed with wires and a battery.
4: When you make hard boiled eggs, what decides whether the yolk is all yellow or if it will have a slightly darker outer portion? Like with Easter eggs, the whole angel/devil scenerio.
lecture preflight 10
1: I agree with student 2 because of the alligator-pool analogy that Joel told us in class. More electricity will flow through circuit B because there are two different paths to choose. So, both bulbs burn just as bright as in circuit A, but there is more flow since two bulbs are being lit brightly and not just one.
2: A/C stands for alternating current and D/C stands for direct current. Alternating Current (AC): A type of electrical current in which the direction of the flow of electrons switches back and forth. In the US, the current that comes from a wall outlet is alternating; it cycles back and forth sixty times each second. The current that flows in a flashlight, on the other hand, is direct current (DC), which does not alternate. Direct Current (DC): Current which moves in a single direction in a steady flow. Normal household electricity is alternating current (AC) which repeatedly reverses its direction. However, many electronics devices require DC, and therefore must convert the current into DC before using it.
3: I thought it was very interesting to see that salt water and baking soda water will conduct electricity, but sugar water and distilled water will not because they dont have charged particles floating around in them.
4: How come if you pause a show on a plasma tv and leave it there paused too long a remainder of the image will stay after you turn the tv off? so what is a plasma tv made of that makes it different from a regular tv?
lecture preflight 10
1: I agree with student 1 because the two different pathways divides up the amount of electricity that is going through it.
2: AC is alternating current, an electrical current whose magnitude and direction vary cyclically but DC is direct current which direction remains constant.
3: That it is the oils on your skin that causes you to gives you and electric shock if by water not the water itself because it would just short the appliance.
4: How can it be colder inside a room when the temperature outside is a lot warmer w/o air conditioning or fans?
lecture preflight 10
1: I agree with student 2. Since the bulbs are the same brightness, we know that they have equal current going through them.
2: A/C stands for alternating current and the current's magnitude and direction vary cyclically. On the other hand, D/C stands for direct current whose direction remains constant.
3: That salt water can conduct electricity.
4: What happens to your body when an electrical current is sent through it (say if you stick your finger in an outlet)?
lecture preflight 10
1: I agree with student 2 because there must be more energy to light up two lightbulbs that have two different paths (as in situation b), and therefore shine equally as bright as situation A. However, the battery will run out faster with situation B.
2: The internet says it has to do with directions the electrons flow. AC switches directions, while DC electrons usually flow in one "foward" direction.
3: I learned how to set up a series and parallel circuit.
4: How does the internet work?
lecture preflight 10
1: i think i agree with student B because lets say the battery is 6 volt, both currents have 6 volts in them while the one current in A has only one 6 volts
2: A/C = alternate source (household electricity) D/C = direct source (battery)
3: you can use salt waiter as a conductor to light a bulb
4: why does a fuse burn out if the voltages from the battery are greater than what the bulb can carry, why is the light bulb just not extra bright?
lecture preflight 10
1: Student 2. The flow must be more in circuit B because the current is the same in A and B, causing the two light bulbs to be equally as bright as the bulb in circuit A.
2: A/C is "Alternating Current." D/C is "Direct Current." Alternating current flows one way and then the other way, constantly reversing direction. Direct current may increase or decrease, but always flows the same direction.
3: I learned that electricity flows from the positive end of a battery to the negative end.
4: How do cellular phones work? To be more specific, how can I send a message to another person without any cords or wires between the phones?
lecture preflight 10
1: Neither because the current through each bulb is the same. In circuit B each light bulb has an independent circuit.
2: A/C is alternating current and D/C is direct current.
3: Circuits and light bulbs produce heat and as a biproduct they produce light.
4: How do cell phones work?
lecture preflight 10
1: Student 2 because figure B is a parallel circuit which means that each bulb is running on an individual circuit.
2: A/C is an alternating current and D/C is direct current.
3: How not to burn myself.
4: I really don't understand the essense of fire.
lecture preflight 10
1: I agree with student A He/She does not indicate the brightness, but it is true that the current through the battery in each circuit is the same.
2: alternating current (A.C.), direct current (D.C.), (http://library.thinkquest.org/15433/unit7/7-4.htm)
3: Currents flow better in parallel ciruits than series circuits.
4: Is it true that an apple a day really keeps the doctor away?
lecture preflight 10
1: I agree with student 2 because in the circuit B each circuit is individual and will be the same brightness because they are both receiving the same amount of volts from the battery.
2: I asked my roomate what the difference between A/C and D/C electricity was and she said she has never heard of either!
3: I learned that salt water conducts electricity!
4: How come when we put the electric current in the water we didnt get electricuted?
lecture preflight 10
1: student 2. Because there's double the amount of current flowing out of the battery for B.
2: "Alternating current or AC electricity is the type of electricity commonly used in homes and businesses throughout the world. While the flow of electrons through a wire in direct current (DC) electricity is continuous in one direction, the current in AC electricity alternates in direction. The back-and-forth motion occurs between 50 and 60 times per second, depending on the electrical system of the country"
3: salt and baking soda conducts electricity
4: none
lecture preflight 10
1: I agree with student 2 because if there were less of a current, the bulb would be dimmer.
2: A/C plugs into an outlet while D/C runs on a rechargeable battery.
3: I did not know that pure water actually does not conduct electricity.
4: If you are holding an umbrella during a thunderstorm and the umbrella gets struck by lightning, could rubber gloves save you?
lecture preflight 10
1: Student 1, because there is same total amount of current for each circuit, meaning in circuit B half of the current is going through each part of the parallel circuit. Even though the lights appear the same, the difference in current is major.
2: In A/C the current is constantly changing directions as it covers distance, while D/C has a direct, constant path for current. A/C is more efficient for long distances, but it is converted into D/C that household appliances use.
3: Distilled water is not a conductor.
4: How do Bluetec diesel engines work? (Audi and Mercedes, made to meet European and California emissions standards)
lecture preflight 10
1: i agree with neither student. all three bulbvs (1 in A, and the 2 in B) will have the same amount of current running through them, thus they will have have the same amount of brighness and the same flow from the battery.
2: alternating current is an electrical current in which the magnitude and direction vary cyclically whereas direct current's direction remains constant
3: the reason you get out of a swimming pool when you see lightening is because the chlorine ion conducts electricity.
4: how does the glaucoma testing machine work?
lecture preflight 10
1: Neither because they both give the wrong argument. Although they are correct in saying that the current in each circuit is the same is correct, they fail to realize that the A and B both have the same brightness in their bulbs because the flow is still the same in both circuits A and B.
2: A/C stands for alternate current and D/C stands for direct current.
3: I learned that distilled water is not a very good conductor of electricity, but that salt and baking soda are because of their charge. I also thought it was really interesting that even though distilled water is not a very good conductor, tap water is, because of all of the stuff in it (minerals, etc.) and that is why you can get electrocuted if an electrical appliance falls into the tub.
4: What is/where from/why is there static electricity?
lecture preflight 10
1: I agree with student 2 because, as we discussed in class, there is twice as much current in circuit B as in circuit A.
2: AC (alternating current) electricity current alternates direction. DC (direct current) electricity current is continuous in one direction.
3: I thought it was interesting in the last activity where we used the different solutions to see if they conducted electricity.
4: Why do the backs of post-its become less sticky over time?
lecture preflight 10
1: student 1 because it is correct, student two needs to go to class more.
2: Alternating current and direct current.
3: Steel wool burns cool if you but a battery to it.
4: Can a can of coke really disolve an entire steak?
lecture preflight 10
1: I agree with B. The brightness is the same, which means that more power (flow) has to go through the circuit.
2: DC is direct current, which means there are electrons moving in one direction only. AC stands for alternating current, and an AC source prodcuts currents that flow in one direction and then the other continuously cycling through.
3: I learned that baking soda conducted electricity.
4: How does an mp3 player work?
lecture preflight 10
1: I agree with student A. It seems logical that there would be less current since they are two bulbs split up.
2: Ac electricity is better for providing electricity. In ac electricity, the current alternates in direction. In Dc electricity the voltages can not be transformed and thats why we use Ac electricity.
3: Water containing Salt or baking soda can help conduct electricity.
4: why doesnt water have a specific shape?
lecture preflight 10
1: I agree with student 2 because B is set-up as parallel circuit so the bulbs are as equally bright as the bulb in A, meaning there is more flow in circuit B.
2: A/C means alternating current which means the current flows one way and then the other. D/C is direct current which means the current always flows in the same direction but it may vary in amount.
3: If you use steel wool as a conductor it starts a fire.
4: Why can humans connect electricty?
lecture preflight 10
1: Student 1 is correct. In circuit A, all of the current must move through it. In B, it has a choice, so it will be split evenly between the two lights.
2: A/C...alternating current. Switches 60 times a second. Lightbulbs and outlets in houses. D/C- Direct current. Things with batteries. Current goes one way...not both.
3: I didn't know that pencil led would conduct electricity.
4: When you split a grape in two and put the two pieces side by side in a microwave, why do they spark?
lecture preflight 10
1: Student 1 is wrong because B has the same amount of brightness in each bulb since it's a parallel circuit. Student 2 is correct because the bulbs all have the same current running through them. However, the flow through the battery in circuit B is not more than circuit A.
2: A/C or alternating current allows electricity to travel far distances without losing much power. A/C voltage can be changed and it also alternates direction. It is most frequently used to power our home appliances, etc. D/C or direct current only allows electricity to travel a short distance before it loses power.
3: Pencil lead and salt water conduct electricity but distilled water doesn't.
4: What minerals in tap water allow conduction of electricity?
lecture preflight 10
1: Neither: B has two independent versions circuits, both with currents that are equally strong and not dividued in half. The flow is the same in A and B, only the current in some places in B is twice as strong.
2: A/C electricity is used for sockets in the house, phones, radio, television. The flow of electrons in D/C electricity is continuous in one directions. The flow of electrons in A/C electricity alternates in direction.
3: Solutions like salt can actually conduct electricity.
4: What solution is the best conductor of electricity and why? And is it also the best conductor of heat?
lecture preflight 10
1: Neither, because when the bulbs are connected in parallel they both have the same brightness. Even though the electricity splits, the same original amount eventually comes back in.
2: A/C stands for alternating current and D/C stands for direct current.
3: Salt water conducts electricity.
4: Could certain kinds of tap water (for example, well water) be conductors of electricity?
lecture preflight 10
1: student 2
2: DC- battery, current goes in one direction. AC- current switches direction many times per minute.
3: how to burn up a light bulb
4: can someone chug a gallon of milk without throwing up?
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1: I agree with Student B, because all of the light bulbs in either A or B will have the same brightness. This is because the current flowing through the light bulbs and the resistance from the light bulbs is the same. In circuit B, more electricity is being used because both of bulbs are glowing at say about 5, whereas in circuit A only one bulb is glowing at 5.
2: A/C stands for alternating current and D/C stands for direct current. In an alternating current, the magnitude and direction of the current change cyclically, whereas in a direct current, the direction remains constant.
3: I learned that electricity always flows from positive to negative but there was no way for me to actually see that happening.
4: How does the weather change so drastically so quickly?
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1: I agree with student one because the voltage and resistance are the same so only the current changes due to V=IR.
2: DC stands for direct current and it is the constant flow of electrons in a single direction. AC stands for alternating current and it is an electrical current whose magnitude and direction vary cyclically. wikipedia.org
3: Christmas lights were originally in a series circuit but now they make them in a parallel so the whole stand does not go out if one light burns out.
4: How do fluorescent lights work?
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1: i agree with student 1- because there is the same current going through both a and b, but because b has two bulds to light up the bulbs will split the total voltage therefore they will be less bright individual when compared to bulb a.
2: A battery cell gives "D.C." or "direct current" which gives a steady voltage to make a radio work. "A.C." stands for "alternating current". The wiring in your house or apartment is AC and all the wiring on the poles outside is AC.
3: i learned that salt water and baking soda were good conductors, but sugar is not.
4: why does hair turn gray?
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1: I think that both are slightly off. The current through the battery in each circuit is the same in both A and B. B is a parallel circuit and each bulb acts independently, thus recieving its full voltage from the battery. That's why the bulbs light up with the same brightness in both circuits. Each bulb gets its equal amount of voltage.
2: A/C is alternating current and D/C direct current. Alternating current is an electric current that reverses direction in a circuit at regular intervals. Direct current is an electric current flowing in one direction only.
3: The difference between parallel and series current. It makes sense that in a parallel current the voltage is transmitted to both bulbs equally.
4: Why do certain fabrics have that when exposed to heat in the dryer, some shrink more than others?
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1: Student 1 because electrons choose their paths. The flow is the same in both circuits.
2: Electricity flows in two ways; either in alternating current or AC and in direct current or DC. The word electricity comes from the fact that current is nothing more than moving electrons along a conductor, like a wire, that have been harnessed for energy. Therefore, the difference between AC and DC has to do with the direction in which the electrons flow. In DC, the electrons flow steadily in a single direction, or "forward." In AC, electrons keep switching directions, sometimes going "forwards" and then going "backwards." The power that comes from our wall outlets is AC, the more common, efficient kind.
3: Pencils can conduct electricity!
4: nothing this week =(
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1: Student 1 because in circuit B the current has two paths that it can follow and so it can split up and in circuit A there is only one path for the current to follow.
2: Alternate current and Direct current. I don't know what exactly the difference is but I guess we will find out in lecture.
3: Pencil is an average conductor of electricity
4: How are Christmas lights set up? Is it a series or a parallel circuit or a combination of both?
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1: I agree with student 1. The current is the same, however the the bulbs in circuit B will be slightly dimmer than the one in circuit A.
2: A/C stands for alternating current, while D/C stands for direct current. The flow of electrons in D/C goes in one direction only, while in A/C it can flow in more than one direction.
3: Even though it can be very dangerous to drop an electrical item in water, water alone does not conduct electricity.
4: What exactly is a calorie?
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1: I agree with Student 1 because in parallel circuits the circuit is the same. Although the flow is divided in circuit B, it eventually regroups and reaches the battery with the same circuit power as it started.
2: DC stands for a direct current where the direction of flow from the current always goes in one direction. AC stands for alternating current where the direction of flow alternates its directions.
3: I learned how to connect a light bulb to a battery and alligator clips and turn the light bulb on.
4: Why do the sidewalks crack at certain points in the year?
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1: I agree with student 1 because the current is going to be the same that runs to the bulbs, but the bulbs in B will be dimmer than that in A because the current has to be split between the two bulbs.
2: The flow of electrons through a wire in direct current (DC) electricity is continuous in one direction, and the current in AC electricity alternates in direction.AC is created by an AC electric generator, which determines the frequency. What is special about AC electricity is that the voltage in it can be readily changed, thus making it more suitable for long-distance transmission than DC electricity.
3: I learned that two bulbs connected to one current will be dimmer than if one bulb is connected to that current.
4: How does temperature affect the sound of a musical instrument?
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1: I do not agree with student one at all because the bulbs in B will both be the same brightness. I partly agree with students two because she explains that both the bulbs in the circuit will have the same brightness; however, I think that there are 2 currents with the same voltage going through the bulbs. If you remove one of the lights it would not effect the other in this parallel circuit.
2: According to http://www.bbc.co.uk/scotland/education/bitesize/standard/other/sos/physics/electricity/answerelectricity_81.shtml, The abbreviation a.c. stands for alternating current and d.c. stands for direct current. As the descriptions suggest, alternating current is current in which the electrons flow in one direction for a time and then they flow in the other direction and so on ie the current alternates. Direct current is current in which the electrons flow in one direction. Alternating current is provided by the mains supply. Direct current is supplied by a battery.
3: I learned that electricity can flow in liquids such as salt water and backing soda.
4: How do cell phones and text messaging actually work? How does the person you are sending a message to actually recieve it?
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1: I don't agree with either student because student 1 is wrong in saying that each bulb has half the current of circuit B and student 2 is wrong in saying that the flow in circuit B is more than A. The voltage is the same and the resistance is the same so the currents are the same.
2: A/C is alternating current, meaning the current changes constantly, flowing left once and then right once. D/C is direct current, meaning it always flows one direction, ie from positive to negative
3: I was reminded of all the things I learned in high school about electricity and current.
4: Why do blood vessels explode?
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1: Neither. The flow of current and the brightness of the bulbs are the same in A and B.
2: A/C=Alternating current D/C=Direct current ...courtesey of my roommate :)
3: I have done this lab in another science class for elementary teachers, but I learned more about currents and how they relate to the brightness of the bulbs.
4: How can the polarity of a microfilament be demonstrated experimentally? a) by adding a fragment containing the myosin tail domain and visualizing by electron microscopy b) by treating cells with fluorescent phalloidin and visualizing by electron microscopy c) by polymerizing green fluorescent actin monomers in the presence of green fluorescent phalloidin-labeled filaments d) by adding a protein fragment containing the myosin head domain and visualizing by electron microscopy e) both c and d are correct Ok, I can't lie, I got this off of my roommate's MCB exam, but it is interesting none-the-less ;)
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1: Neither, the current through circuit B is larger. This is true because the current still only hast o go through one bulb but it can go through either. Therefore the current is larger in circuit B.
2: A/C is alternating current electricity and D/C is direct current electricity. D/C electricity is the continuous movement of electrons from an area of negative (-) charges to an area of positive (+) charges through a conducting material such as a metal wire. A/C electricity alternates in direction.
3: I learned that they wire gets hot if the ends of it are connected to both ends of the battery.
4: Why do cans of pop sometimes explode when they freeze?
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1: i agree with the second student because we said that brightness is determined by current.. more current=brighter.. so if all bulbs have the same brightness then there should be the same current going through them.
2: D/C means direct current and A/C means alternate current. with a D/C it is not possible to use a transformer to change voltage. A/C also provides advantages in the designs of motors and generators
3: pencil lead (graphite) is a conductor
4: our group was confused as to why the light bulb didn't go off when we put each of the ends on ourselves..if we're not conductors why can we get struck by lightening
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1: Neither. I almost agree with student 2, but the current going through them both is the same.
2: A/C stands for alternating current and D/C stands for direct current. The flow of electrons in A/C electricity sometimes changes directions, but D/C electricity means that the electrons stay flowing in the same direction.
3: I learned how lightbulbs work.
4: How does a computer send things to a printer and print them out so fast?
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1: I agree with student 1 because current always remains the same. It never gets used up or taken away therefore, the amount of total current in the battery in each circuit is the same, however, the current is divided between the 2 bulbs in circuit B since it is parallel.
2: A/C electricity is alternating current and is the most often used in homes. DC electricity provides direct current and is continuous in one direction while AC electricity alternates in direction.
3: I learned that baking soda conducts electricity.
4: I was wondering why lead pencil did not conduct electricity?
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1: I agree with student 1. This is because the current flowing through the battery in each of the circuits has to be the same. The only difference is the current flowing through the bulbs in circuit A and circuit B. Circuit A has the same current flowing through the bulb as the battery because they are in series. In B, the current is divided according to resistance among all parallel components. The more resistance the component has, the less current it shall receive.
2: A D/C electricity or Direct current electricity involves current flowing in one direction. In A/C electricity or Alternating current electricity, the voltage alternates in a sine wave pattern instead of just the constant voltage as in the case of A/C circuit.
3: I thought it was really interesting to see how baking soda acted as a conductor. I thought the bulb would not light up in baking soda because because it is more of a basic solution when mixed with water.
4: How do they time the tiny bulbs in christmas lights that blink on and off continously?
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1: I agree with Student 1. The battery provides the same amount of current, which is divided between the two bulbs.
2: D/C electricity is direct current electricity and can only carry the electric current a minimal distance, but A/C, or alternating current, can carry the electric current much further.
3: I learned that salt water can be light conductor.
4:
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1: neither. i think they would both be about the same (circuits a and b) if not b has to split the electricity between the 2 bulbs so it would be less
2: a/c electricity stands for alternating current while d/c stands for direct current.
3: distilled water does not conduct electricity but salt water will
4: how much electricity does lightening have?
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1: Neither. The light bulbs will be the same brightness in both A and B, but the current is not the same in both.
2: A/C is alternating current and D/C is direct current. D/C has an offset which A/C doesn't (centered at 0)
3: The graphite in a pencil conducts electricity.
4: How can it be so warm, get so cold so quickly, and then everyone gets sick?
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1: Student two because the current passes through both at the same time and meets at the end to flow back to the beginning.
2: A/C stands for alternating current and D/C stands for direct current.
3: Salt water conducts electricity.
4: How/when/will the sun burn out?
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1: student 2; the current is the same everywhere, regardless of how many bulbs there are.
2: a/c is alternating circuit and d/c is direct curcuit. i found this site that explains it all but i still dont understand... http://www.satcure-focus.com/tutor/page1.htm
3: i knew nothing about circuits!
4: why does gravity work? what is actually pulling us? why does the earth have gravity?
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1: I agree with neither of the students. Student one was correct in that they said that the current through each of the circuits is the same and the flow is the same. Student B is wrong in that they say that the flow through battery in circuit B is more. I think that the current and flow through each battery of each circuit is the same. The bulbs will also be of equal brightness because they each are receiving the same amount of flow because they all are part of a closed circuit.
2: A/C is alternating current and D/C is direct current. Direct current means that you are receiving a steady flow of voltage in one direction to whatever object you are using. Alternating current goes in alternating directions. The voltage can also be changed, thus it works better for long distances.
3: I learned the water pipe analogy of currents and electricity which helped me to better understand resistence.
4: How do heaters work?
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1: I agree with student number 1. The circuit is the same but it is simply divided to be able to supply the two lightbulbs with the same amoung of energy. However, the first circuit( A) will shine brighter since it is the only light bulb in the series.
2: A/C stands for alternating current while D/C stands for direct current. What this means is that A/C has no specific temperature while D/C has to function at a specific in order to function as smoothly as it should. This affects the distance of how long the electricity can flow without loosing energy. When comparing these two AC is used to further and stronger currents while DC is used for things that might need less energy to function.
3: One intresting thing that I leaned in lab this week is that a distilled water is not as good as a condutor of electricity as tap water.
4: How do DVD players work?
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1: Neither. B would shine brighter but not because the flow through the battery in circut B is more than through the battery in circut A, but because it is the same.
2: A/C stands for alternating current and D/C stands for direct current.
3: I learned what conducts electricity well and what doesn't.
4: How do scientists find the calories of a food?
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1: student B because like joel said the flow of traffic would be lighter and there would be more options to reroute, with no traffic jam.
2: well i have no clue! i tied looking it up and it only gave me ways to monitor it.... BUT my brother told me that the electric slide is a great way to demo electricity.
3: salt conducts energy! and the pool connection(chlorine being a good condutor also) !
4: IS the electric slide is it really a good representation for the way electricity work? maybe we should have class participation to dance.... MATS YOU BRING THE MUSIC! "how many wood chuck can a wood chuck chew if a wood chuck could chuck wood?" where did this silly thing come from??
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1: Student 2 is correct becuase B passes twice as much current as A to reach both batteries.
2: A/C is an alternating current, while D/C is a direct current.
3: I learned the difference between a series and a parrel circuit.
4: Why do plugs sometimes spark when you plug things in??
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1: I agree with neither. The flow of the current is the same in both circuits. This is evident because all of the bulbs in this circuit will light up with the same brightness.
2: A/C (alternating current) electricity flows one way and then the other way, continually alternating its flow. A/C electricity can be distributed much farther thatn D/C electricity. D/C (direct current) electricity always flows in the same direction. It is always positive or always negative unlike A/C electricity that can change between the two.
3: Sugar is not a good conducter.
4: How does a police radar gun work?
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1: Student 2 because although the energy is split there just needs to be more power supplied to circuit B (the battery will die quicker) but the same brightness will show.
2: DC - direct current means electrons only move in one direction. Where as AC - alternating current where currents flow in more than one direction.
3: The analogy of water and electricy helped me to understand how current flows and how the battery plays into the electical circuit.
4: How do halogen light bulbs work as opposed to "regular" light bulbs?
lecture preflight 10
1: I agree with student 1. The current from the battery is divided up between the two bulbs to equal the total amount as if there was only one bulb.
2: Alternating current (AC) is an electrical current whose magnitude and direction can change. Direct current (DC) is an electrical current whose direction remains the constant.
3: I thought it was interesting that the distilled water was not a conductor of electricity but the salt water was.
4: My friend was saying that his football coach use to recommend eating bananas. Why?
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1: I agree with student B, because the current is not divided in hald in B, because the light bulbs are not on the same pathway.
2: Alternating current or AC electricity is the type of electricity commonly used in homes and businesses throughout the world. While the flow of electrons through a wire in direct current (DC) electricity is continuous in one direction, the current in AC electricity alternates in direction.
3: I learned that pencil lead is a good conductor of electricity.
4: How does snow form?
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1: I agree with Student 2 because circuit B is a parallel circuit. Parallel circuits are made of two indentical, independent cicruits that have the same amount of electric current through them.
2: D/C is a direct current in which electricity is flowing in a constant direction and has a voltage of constant polarity (like a battery with definite +/- terminals). A/C stands for alternating current. These electrical sources naturally produce alternating voltage poles and reverse over time. Currents can also switch back and forth as well.
3: I learned that baking soda and salt can conduct electricity.
4: How do fireworks work?