The peak voltage of an ac supply is 300 V. What is the rms voltage? (b) The rms value of current in an ac circuit is 10 A. What is the peak current?
Solution and Explanation
(a) Peak voltage of the ac supply, V0 = 300 V
rms voltage is given as:
\(V= \frac{V°}{√2} = \frac{300}{√2}=212.1\)
(b) The rms value of current is given as:
I = 10 A
Now, peak current is given as:
\(I°= √2I = √2 × 10 = 14.1A\)
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Concepts Used:
AC Voltage
When voltage changes its direction after every half cycle is known as alternating voltage. The current flows in the circuit at that time are known as alternating current. The alternating current(AC) follows the sine function which changes its polarity concerning time. Most of the electrical devices are operating on the ac voltage.
