Question 25 of 190

The current flowing through an ac circuit is given by $I=5\sin \left(120\pi t\right)A$. How long will the current take to reach the peak value starting from zero?

A$\dfrac{1}{60}s$B$60s$C$\dfrac{1}{120}s$D$\dfrac{1}{240}s$

Show answer and solution▾

Answer: (D) $\dfrac{1}{240}s$

If initial value of current is zero, then it will take $\dfrac{T}{4}$ time to reach the peak value, where $T=$ time period.
As we know, $\omega =120\pi$
Therefore,
$t=\dfrac{T}{4}=\dfrac{\dfrac{2\pi }{\omega }}{4}$ $=\dfrac{\pi }{2\omega }=\dfrac{\pi }{2\times 120\pi }=\dfrac{1}{240}s$

JEE Main Physics practice question on Alternating Current (Alternating Current, Voltage and Power), with the answer and a step-by-step solution. Scan a question from your own book or paper to get a whiteboard video.