Question

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

• A. $\frac{1}{60} s$
• B. $60 \;s$
• C. $\frac{1}{120} s$
• D. $\frac{1}{240}s$

Answer 1

Answer: (D)

$\frac{1}{240}s$

Answer 2

$ω = 120π$

$⇒T=\frac{1}{60}\;sec$

The current will take its peak value in $(\frac{T}{4})$ time

$t=\frac{T}{4}$

= $\frac{1}{240}$ $s$

Hence, the correct option is (D): $\frac{1}{240}$ $s$