An alternating current of frequency $50 \mathrm{~Hz}$ has the peak value as $14 \cdot 14 \mathrm{~A}$. The…

An alternating current of frequency $50 \mathrm{~Hz}$ has the peak value as $14 \cdot 14 \mathrm{~A}$. The time taken by the alternating current in reaching from zero to maximum value and r.m.s. value of current will be respectively
  1. $0.025 \mathrm{~s}, 5 \mathrm{~A}$
  2. $0 \cdot 005 \mathrm{~s}, 5 \mathrm{~A}$
  3. $0 \cdot 005 \mathrm{~s}, 10 \mathrm{~A}$
  4. $0 \cdot 025 \mathrm{~s}, 10 \mathrm{~A}$

Solution

$\mathrm{f}=50 \mathrm{~Hz}, \mathrm{~T}=\frac{1}{50} \mathrm{~s}=0.02 \mathrm{~s}$ Time taken to reach from zero to maximum value is $\begin{array}{l} t=\frac{T}{4}=\frac{0.02}{4}=0.005 \mathrm{~s} \\ I_{m s}=\frac{I_{0}}{\sqrt{2}}=\frac{14.14}{1.414}=10 \mathrm{~A} \end{array}$

Asked in: MHT CET 2020 (19 Oct Shift 1)

Practice more Alternating Current questions on Aicharya