Question

Assertion : A series combination of cells is used when their internal resistance is much smaller than the external resistance.

Reason : It follows from the relation $I=\frac{nE}{R+nr}$, where the symbols have their standard meaning.

• A. Both (A) and (R) are true and (R) is the correct explanation of A
• B. Both (A) and (R) are true but (R) is not the correct explanation of A
• C. (A) is true but (R) is false
• D. (A) is false but (R) is true

Answer 1

The correct option is A Both (A) and (R) are true and (R) is the correct explanation of A

When our aim is to draw more current and if the the internal resistance in same compared to $R$, then if is best to use series combination

$\Rightarrow I=\frac{nE}{R+nr}$

$\Rightarrow I=\frac{nE}{R}[\because r<R]$