Question

If $q=2t^2+3$, find current at $t=2\text{s}$.

• A. $1\text{A}$
• B. $2\text{A}$
• C. $4\text{A}$
• D. $8\text{A}$

Answer 1

The correct option is D $8\text{A}$

We know that, electric current,
$$i=\frac{dq}{dt}$$Here, $q=2t^2+3$

Therefore, $i=\frac{d(2t^2+3)}{dt}=4t$

At $t=2\text{s}$, $i=4\times 2=8\text{A}$

Key takeaway: Electric current, $i=\frac{dq}{dt}$