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# Physics multiple choice help watch

1. Hi i'm stuck on this question and cant understand the theory behind it could someone please help me?

Question:

A pd V is applied across a resistor. Another identical resistor is then connected in
series with it and the same pd V is applied across the combination.
Which statement is incorrect?

A The total resistance is doubled.
B The pd across one resistor is 2
V .
C The current in the resistors is halved.
D The power dissipated in one resistor is halved.

So I get why D is the answer. But wouldn't C be incorrect as well? Becuase it says it's connected in series and current isn't shared in series.

Any help is greatly appreciated thank you!
2. (Original post by assassinjeev22)
Hi i'm stuck on this question and cant understand the theory behind it could someone please help me?

Question:

A pd V is applied across a resistor. Another identical resistor is then connected in
series with it and the same pd V is applied across the combination.
Which statement is incorrect?

A The total resistance is doubled.
B The pd across one resistor is 2
V .
C The current in the resistors is halved.
D The power dissipated in one resistor is halved.

So I get why D is the answer. But wouldn't C be incorrect as well? Becuase it says it's connected in series and current isn't shared in series.

Any help is greatly appreciated thank you!
I don't thing B is correct either - if the PD across both resistors is V the PD across one of the resistors can't be 2V... have you copied the question incorrectly?

---

C is correct though - the effective resistance of the two resistors in series is the sum of their resistances. if the resistors are equal resistance the 2 in series have double the resistance of one resistor on it's own.
If the applied PD is the same then current must be halved because I=VR. Doubling R and keeping V the same means I is halved.
3. (Original post by Joinedup)
I don't thing B is correct either - if the PD across both resistors is V the PD across one of the resistors can't be 2V... have you copied the question incorrectly?

---

C is correct though - the effective resistance of the two resistors in series is the sum of their resistances. if the resistors are equal resistance the 2 in series have double the resistance of one resistor on it's own.
If the applied PD is the same then current must be halved because I=VR. Doubling R and keeping V the same means I is halved.
Oh yeah B didnt copy correctly its meant to be V/2. Thank you!

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