Question

An ac source is rated at $220V$, $50Hz$. The time taken for voltage to change from its peak value to zero is

• A. $50sec$
• B. $0.02sec$
• C. $5sec$
• D. $5\times {10}^{-3}sec$

Answer 1

The correct option is D $5\times {10}^{-3}sec$

As we know,

Required time for ac to reach it's peak value is $t=\frac{T}{4}$
$=\frac{1}{4\times f}=\frac{1}{4\times 50}=5\times {10}^{-3}sec$