Question

Calculate the amount of charge flowing in $2\text{min}$ in a wire of resistance $10\Omega$ when a potential difference of $20\text{V}$ is applied between its ends.

• A. $120\text{C}$
• B. $240\text{C}$
• C. $180\text{C}$
• D. $4\text{C}$

Answer 1

The correct option is B $240\text{C}$

Given:
$R=10\Omega ;V=20\text{V};t=2\text{min}$

As we know that

Current, $I=\frac{q}{t}=\frac{V}{R}$

$\therefore q=\frac{Vt}{R}=\frac{20\times 2\times 60}{10}$

$\Rightarrow q=240\text{C}$

Hence, option $\left(b\right)$ is correct.

Key takeaway- electric current through an area is the rate of transfer of charge from one side of the area to the other. Current can be found using Ohms law. $V=IR$