Q. The amount of charge $Q$ passed in time $t$ through a cross-section of a wire is $Q = 5t^{2} + 3t + 1.\ $The value of current at time $t = 5$s is
A) 9 A
B) 49 A
C) 53 A
D) None of the above
Explanation
(c) Current, $i = \frac{d\mathcal{Q}}{dt} = \frac{d}{dt}\left( 5t^{2} + 3t + 1 \right) = 10t + 3$
When t=5s
$\ \ \ \ \ \ \ \ \ \ \ \ i = 10 \times 5 + 3 = 53A$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.