An alternating current varying sinusoidally, with a frequency of 50 Hz has an RMS value of 20 A. Write down the equation for the instantaneous value and find this value at (a) 0.0025 s, and (b) 0.0125 s after passing through a positive maximum value. At (a) 0.0025 s, and (b) 0.0125 s after passing through a positive maximum value. At what time, measured from a positive maximum value, will the instantaneous current be 14.14 A?

Find the rms value of 7, 10, 13. (Round off to the tenth)

3. Write the sinusoidal expressions for voltages and currents having the following rms values at a frequency of 60 Hz with zero phase shift: a) 10 V, b) 2KV , c) 50 mA 4. The current through a. 0.1 H coil is given. What is the sinusoidal expression for the voltage? a) 10 sin100t b) 6 x 10-3 sin377t c) - 4 cos(20t – 70')

1. Derive the formula for the RMS value for the following a) tespe RSITY SAIN

The rms current in a 33.0-0 resistor connected to an AC source is 2.80 A. (a) What is the rms voltage across this resistor? V (b) What is the peak voltage of the AC source? V (c) What is the average power dissipated by the resistor? W (d) What is the maximum current across this resistor? A

The equation of alternating voltage isgiven by ν = 325.22 ???314?.Find (i) RMS value (ii) Frequency (iii)Average value.

4. The waveform of a sinusoidal voltage is shown as Vin(t) 2V -2V+ (a) Determine the equation of the sinusoidal voltage. (Note that the unit of time is in milliseconds) (b) If the sinusoidal voltage is applied on a 1022, determine the power dissipated by the resistor. 14 t, ms (c) Determine the time in the first cycle at which the value sinusoidal voltage is 0.6V. (c) Draw the waveform of VD(t) and Vr(t) if the sinusoidal voltage is applied as input to a diode circuit as shown. Use ideal diode approximation. Vin D ID

Add the two voltages below together (phasor voltages are RMS). ?ଵ =60 ? ∠ 0° ?ଶ =80 ?∠ 270° a) What is the resultant as a phasor using RMS voltage and degrees? b) What is the resultant voltage as a sinusoidal equation if the frequency is 100 Hz?

RMS value of an alternating current is 30 A and its frequency is 25 Hz. Write its equation to find its instantaneous value. Calculate also (1) its average value and (2) time period.