Question 349: AC fundamentals

Question

The magnetic energy in an inductor changes from maximum value to minimum value in 5 ms . When connected to an a.c. source, the frequency of the source is

Accepted Answer

Magnetic field energy changes from maximum to minimum in $\frac{1}{4}^{	ext {th }}$ time of a cycle
$$\begin{aligned}
	herefore \quad & \frac{\mathrm{T}}{4}=5 \mathrm{~ms} \Rightarrow \mathrm{~T}=20 \mathrm{~ms} \
\mathrm{f} & =\frac{1}{\mathrm{~T}}=\frac{1}{20 	imes 10^{-3}}=50 \mathrm{~Hz}
\end{aligned}$$

Answer

50 Hz

Answer

200 Hz

Answer

500 Hz

Answer

20 Hz

AC fundamentals

The magnetic energy in an inductor changes from maximum value to minimum value in 5 ms . When connected to an a.c. source, the frequency of the source is

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