First slide

Electrical Resonance series circuit

Question

In the circuit shown in the figure, the ac source gives a voltage $20\cos (2000t)$ Neglecting source resistance, the voltmeter and ammeter reading will be

Moderate

A

0V, 0.47A
B

1.68V, 0.47A
C

0V, 1.4 A
D

5.6V, 1.4 A

Solution

$Z = \sqrt {{{(R)}^2} + {{({X_L} - {X_C})}^2};}$
$R = 10\,\Omega ,\,\,{X_L} = \omega L = 2000 \times 5 \times {10^{ - 3}} = 10\,\Omega$
${X_C} = \frac{1}{{\omega C}} = \frac{1}{{2000 \times 50 \times {{10}^{ - 6}}}} = 10\,\Omega \,\,i.e.\,Z = 10\,\Omega$
$Maximum\,current\,\,{i_0} = \frac{{{V_0}}}{Z} = \frac{{20}}{{10}} = 2A$
$Hence\,\,{i_{rms}} = \frac{2}{{\sqrt 2 }} = 1.4\,A$
$and\,\,{V_{rms}} = 4 \times 1.41 = \,5.64\,\,V$

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App