Question

An alternating e.m.f. of $E=100\sin (100\pi$t ) is connected to a choke of negligible resistance and current oscillations of amplitude 1 A are produced. The inductance of the choke should be

• A. $100H$
• B. $\frac{1}{\pi }H$
• C. $1H$
• D. $\pi H$

Answer 1

Answer: (B)

$\frac{1}{\pi }H$

Angular frequency $\omega =100\pi$

Reactance $X_L=100\pi \times L$

$I_o=1A$

$E_o=100V$

$\therefore \frac{E_o}{X_L}=\frac{100}{100\pi \times L}=1$

$L=\frac{1}{\pi }H$