Question

A battery of $2V$ emf and internal resistance $1\Omega$ sends a current of $1A$ through an external load. If two such batteries are connected in series, the current through same load is

• A. 1 A
• B. 1.33 A
• C. 1.5 A
• D. 2.0 A

Answer 1

Answer: (B)

Let $R=$ External resistance
$I=\frac{2}{1+R}($ first case $)\therefore R=1\Omega$
When two batteries are connected emf becomes
$4V$ and internal resistance $2\Omega .$
$I=\frac{4}{1+2}=\frac{4}{3}=1.33A$