Question

- Two equal resistors R connected in series across a voltage source
V dissipate power P. What would be the power dissipated in the
same resistors when they are connected in parallel across the
voltage source
A. 4P
B.P
C.2P
D. 16P
​

Answer 1

Answer:

2p is the correct answer

please mark as brainliest

Answer 2

❖ For series connection :

Two equal resistors of R are first connected in series across a voltage source V.

• Power dissipated = P

First of all we need to find equivalent resistance of the series connection.

➙ Rs = R + R

➙ Rs = 2R

Let's calculate power dissipated by resistors.

➙ P = V²/Rs

➙ P = V²/2R .......... (I)

❖ For parallel connection :

Two equal resistors of R are then connected in parallel across a voltage source V.

• We are asked to find power dissipated in forms of P$.$

Equivalent resistance of parallel connection is given by

➙ 1/Rp = 1/R + 1/R

➙ 1/Rp = 2/R

➙ Rp = R/2

Power dissipated by resistors :

➙ P' = V²/Rp

➙ P' = V²/(R/2)

➙ P' = 2V²/R

From the (I) equation, V²/R = 2P

➙ P' = 2 × 2P

➙ P' = 4P

∴ (A) is the correct answer!