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An alternating voltage \(V(t)=220 \sin 100 \pi t\) volt is applied to a purely resistive load of \(50 \Omega\). The time…

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An alternating voltage \(V(t)=220 \sin 100 \pi t\) volt is applied to a purely resistive load of \(50 \Omega\). The time taken for the current to rise from half of the peak value to the peak value is:

a

\(2.2 ms\)

b

\(7.2 ms\)

c

\(3.3 ms\)

d

\(5 ms\)

✓ Correct answer: c)

\(3.3 ms\)

Explanation

\(i(t)={i}_{0}\sin 100\pi t\)

\(\frac{{i}_{0}}{2}={i}_{0}\sin 100\pi {t}_{1}\)

\(\sin 100\pi {t}_{1}=\sin \frac{\pi }{6}\)

\(100\pi {t}_{1}=\frac{\pi }{6}\)

\({t}_{1}=\frac{1}{600}\text{sec}\)

Similarly \({t}_{2}=\frac{1}{200}\text{sec}\)

\(t={t}_{2}−{t}_{1}\)

\(=\frac{1}{200}−\frac{1}{600}\)

\(t=\frac{3−1}{600}=\frac{1}{300}\)

t = 3.3 ms

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