JEE MainPhysicsCurrent ElectricityMCQ+4 / −1
The figure shows three circuits I, II and III which are connected to a 3V battery. If the powers dissipated by the configurations I, II and III are P1 , P2 and P3 respectively, then : 

- AP1 > P2 > P3
- BP1 > P3 > P2
- CP2 > P1 > P3
- DP3 > P2 > P1
View written solutionFree
Correct answer: C
To compare the powers, we use the fact that all three configurations are connected across the same battery voltage .
For a fixed voltage source, So, smaller equivalent resistance means larger power.
1. Find equivalent resistance of each circuit
From the figure, each circuit is made of identical resistors of resistance .
Circuit I
This is the series combination of two resistors:
Hence,
Circuit II
This is a parallel combination of two identical resistors:
Hence,
Circuit III
This is a single resistor of resistance connected across the battery, so
Hence,
2. Compare the powers
We have
Therefore,
3. Check the options
- A: ❌
- B: ❌
- C: ❌
- D: ❌
The correct order is
So none of the listed options matches this order.
4. Comparison with stored correct answer
Stored correct answer: C
But our derived result is: which does not match option C.
Therefore, I disagree with the stored answer.
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