Question

A voltmeter is connected in parallel with a variable resistance $R$ which is in series with an ammeter and a cell as shown in the figure. For one value of $R$, the meters read $0.3A$ and $0.9V$. For another value of $R$ the readings are $0.25A$ and $1.0V$. What is the internal resistance of the cell?

• A. $0.5\Omega$
• B. $2\Omega$
• C. $1.2\Omega$
• D. $1\Omega$

Answer 1

Answer: (B)

$r=\frac{10}{5}=2r$