MCQ
An alternating voltage $E = 200\sqrt 2\, \sin\, (100\,t)$ is connected to a $1$ microfarad capacitor through an ac ammeter. The reading of the ammeter shall be......$mA$
- A$10$
- ✓$20 $
- C$40 $
- D$80$
✓
Answer
Correct option: B.
$20 $
b
(b) Reading of ammeter $ = {i_{rms}} = \frac{{{V_{rms}}}}{{{X_C}}} = \frac{{{V_0}\omega C}}{{\sqrt 2 }}$
$ = \frac{{200\sqrt 2 \times 100 \times (1 \times {{10}^{ - 6}})}}{{\sqrt 2 }} = 2 \times {10^{ - 2}}A = 20\;mA$
(b) Reading of ammeter $ = {i_{rms}} = \frac{{{V_{rms}}}}{{{X_C}}} = \frac{{{V_0}\omega C}}{{\sqrt 2 }}$
$ = \frac{{200\sqrt 2 \times 100 \times (1 \times {{10}^{ - 6}})}}{{\sqrt 2 }} = 2 \times {10^{ - 2}}A = 20\;mA$
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