Need help veryfing E&M Multiple Choice

AI Thread Summary
The discussion revolves around verifying multiple-choice questions related to electric circuits involving resistors and lightbulbs. It confirms that the current in a circuit can be approximated by assuming zero resistance in the wires, while the voltage drop across the wires is not the same as across other elements due to their small resistance. The responses clarify that wires A, B, and C can be treated as having zero resistance, and both lightbulbs L1 and L2 will experience the full power supply voltage. Additionally, it is noted that L1 and L2 will carry current, contradicting the assumption that they would have zero current. The conversation highlights confusion regarding circuit analysis, particularly with wires that have resistance.
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Need help verifying E&M Multiple Choice

(True/false) (Referring to a diagram that is an ideal battery with wires connecting the positive and negative ends to a resistor in the form of a lightbulb of 30 ohm resistance creating a circuit). I'm also fairly sure the wires resistances are 0.1 ohm
-To a good approximation the current in the circuit can be calculating assuming wires have zero resistance. True?
-To a good approximation the voltage drop across the wires will be the same as that across the other circuit elements. False?
-To a good approximation the voltage across any other element in the circuit will be the same as if the wires actually did have zero resistance. True?

These next ones refer to a circuit like the above except there's a wire (Wire B) that connects from just outside the positive wire (wire A) running into the lightbulb (L2) to just outside the negative wire (Wire C) running into the lightbulb. There's also now a lightbulb(L1) spliced into the positive wire (wire A). Also, assume the wires have a low resistance compared to the lightbulbs.

-To a good approximation, wires A, B and C can all be taken to have zero resistance. True?
-To a good approximation, only wires A and C will carry current and wire B carries almost no current. False?
-To a good approximation, L1 will have a full power supply across it. True?
-To a good approximation, L2 will have the full power supply voltage across it. True?
-To a good approximation, L1 will have 0 current. False?
-To a good approximation, L2 will have 0 current. False?

I'm so confused. These prelab questions made me read ahead in the book but no examples in the book take into account wires with resistance! The book just sort of skips over circuits and goes right into Magnetism.

Edit I only have mspaint to make a drawing in so I don't know if it would help any.
 
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Hello,

I would be happy to help you verify these multiple choice questions. Here are my responses:

1. True - To a good approximation, the current in the circuit can be calculated assuming the wires have zero resistance. This is because the resistance of the wires is very low compared to the resistance of the lightbulb, so it can be neglected in the calculation.

2. False - To a good approximation, the voltage drop across the wires will not be the same as that across the other circuit elements. This is because the wires do have some resistance, so there will be a small voltage drop across them. However, this voltage drop will be very small compared to the voltage drop across the lightbulb, so it can be neglected in the calculation.

3. True - To a good approximation, the voltage across any other element in the circuit will be the same as if the wires actually did have zero resistance. This is because the voltage drop across the wires is very small, so it can be considered negligible in the calculation.

4. True - To a good approximation, wires A, B, and C can all be taken to have zero resistance. This is because the wires have a low resistance compared to the lightbulbs, so their resistance can be neglected in the calculation.

5. False - To a good approximation, only wires A and C will carry current and wire B carries almost no current. This is not true because wire B is connected in parallel with the lightbulb L2, so it will also carry some current.

6. True - To a good approximation, L1 will have a full power supply across it. This is because L1 is connected in series with the power supply and there is no other resistance in the circuit, so the full voltage of the power supply will be across L1.

7. True - To a good approximation, L2 will have the full power supply voltage across it. This is because L2 is connected in series with the power supply and the wires have very low resistance, so the full voltage of the power supply will be across L2.

8. False - To a good approximation, L1 will have 0 current. This is not true because L1 is connected in series with the power supply and there is no other resistance in the circuit, so it will have the same current as the power supply.

9. False - To a good approximation, L2 will have 0 current. This is not true because
 


Sure, I'd be happy to help verify these multiple choice questions about E&M circuits. Here are my answers:

1. True - To a good approximation, the current in the circuit can be calculated assuming the wires have zero resistance. This is because the resistance of the wires is much smaller than the resistance of the lightbulb, so it can be neglected in the calculations.

2. False - To a good approximation, the voltage drop across the wires will not be the same as that across the other circuit elements. This is because the wires do have a small resistance, so there will be a voltage drop across them, but it will be much smaller than the voltage drop across the lightbulb.

3. True - To a good approximation, the voltage across any other element in the circuit will be the same as if the wires actually did have zero resistance. This is because the voltage drop across the wires is small and can be neglected in the calculations.

4. True - To a good approximation, wires A, B, and C can all be taken to have zero resistance. This is because the resistance of the wires is small compared to the resistance of the lightbulbs, so it can be neglected in the calculations.

5. False - To a good approximation, only wires A and C will carry current and wire B carries almost no current. This is not necessarily true, as the current will flow through the path of least resistance. In this case, wire B may carry some current, but it will be much smaller than the current through wires A and C.

6. True - To a good approximation, L1 will have a full power supply across it. This is because L1 is connected directly to the power supply and has no resistance in its path.

7. True - To a good approximation, L2 will have the full power supply voltage across it. This is because L2 is also connected directly to the power supply and has no resistance in its path.

8. False - To a good approximation, L1 will have 0 current. This is not necessarily true, as L1 is connected directly to the power supply and will have some current flowing through it, although it may be small compared to the current through L2.

9. False - To a good approximation, L2 will have 0 current. This is not necessarily true, as L2 is connected to the power supply through the lightbulb L1. So, there will be some current
 
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