First a set of n equal resistors of R each is connected in series to a battery of emf E and internal resistance R. A current I is observed to flow. Then the n resistors are connected in parallel to the same battery. It is observed that the current becomes 10 times. What is ‘n’?

Question

Philoid · Accepted Answer

When n resistors are in series and internal resistor is also R, then current value is,

.

When resistors are in parallel, the current becomes,

.

According to the question, I’=10I.

So,

.

Thus, n =10.