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Current Electricity

JEE Main level, single correct, medium

170 of 380

Question 170 of 380

For the two cells having same EMF $E$ and internal resistance $r$ , the current passing through the external resistor $6 \Omega$ is same when both the cells are connected either in parallel or in series. The value of internal resistance $r$ is $\_\_\_\_$ $\Omega$ .

Show answer and solution

Answer: (A) 6

For series connection of two cells:

I_s = \frac{2E}{2r + 6}

.
For parallel connection:

I_p = \frac{E}{r/2 + 6} = \frac{2E}{r + 12}

.
Given

I_s = I_p

\frac{2E}{2r + 6} = \frac{2E}{r + 12}

.
This gives

2r + 6 = r + 12

, so

r = 6\Omega

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JEE Main Physics practice question on Current Electricity (Electric Cell or Battery), with the answer and a step-by-step solution. Scan a question from your own book or paper to get a whiteboard video.

For the two cells having same EMF EEE and internal resistance rrr, the current passing through the external resistor 6Ω6 \Omega6Ω is same when both the cells are connected either in parallel or in series. The value of internal resistance rrr is ____\_\_\_\_____ Ω\OmegaΩ.

JEE Main question paper PDF

More Physics practice

For the two cells having same EMF $E$ and internal resistance $r$ , the current passing through the external resistor $6 \Omega$ is same when both the cells are connected either in parallel or in series. The value of internal resistance $r$ is $\_\_\_\_$ $\Omega$ .