282.8 V
200 V
141.4 V
127.4 V

## AC Fundamentals, Circuit and Circuit Theory The r.m.s. value of pure cosine function is

0.707 of peak value
Same as peak value
0.5 of peak value
Zero

## AC Fundamentals, Circuit and Circuit Theory The phase difference between voltage and current wave through a circuit element is given as 30°. The essential condition is that

None of the listed here
Both waves must have zero value at the same time
Both waves must have identical peak values
Both waves must have same frequency

## AC Fundamentals, Circuit and Circuit Theory The time constant of the capacitance circuit is defined as the time during which voltage

Rises to 38.6% of its final steady value
None of these
Falls to 36.8% of its final steady value
Rises to 63.2% of its final steady value

Non-oscillating
Sinusoidal
Oscillating
Square wave

## AC Fundamentals, Circuit and Circuit Theory The effective resistance of an iron-cored choke working on ordinary supply frequency is more than its true resistance because of

Capacitive effect between adjacent coil turns
Iron loss in core
Skin effect
Increase in temperature