A. There is a sinusoidal current i(t) that has an rms value of 20 A, a period of 1 ms, and reaches a positive peak at t = .3 ms, write an expression for i(t). B. The voltage v(t) = 10 sin(250π(t)) V appears across a 20 ohm resistance. Sketch v(t) and p(t) to scale versus time. Find the average power delivered to the resistance.

A. There is a sinusoidal current i(t) that has an rms value of 20 A, a period of 1 ms, and reaches a positive peak at t = .3 ms, write an expression for i(t). B. The voltage v(t) = 10 sin(250π(t)) V appears across a 20 ohm resistance. Sketch v(t) and p(t) to scale versus time. Find the average power delivered to the resistance.

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter2: Fundamentals

Section: Chapter Questions

Problem 2.27P: An industrial load consisting of a bank of induction motors consumes 50 kW at a power factor of 0.8...

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An industrial load consisting of a bank of induction motors consumes 50 kW at a power factor of 0.8 lagging from a 220-V,60-Hz, single-phase source. By placing a bank of capacitors in parallel with the load, the resultant power factor is to be raised to 0.95 lagging. Find the net capacitance of the capacitor bank in F that is required.
(b) An engineer is required to analyse a sinusoidal waveform for the voltage and current using oscilloscope. The voltage waveform produced Root Mean Square (RMS) value at 75 V with positive-going zero crossing at 30°. While the RMS value of current is 66.71 A with negative-going zero crossing at 0.349 rad. Assume the frequeney of both waveforms is 50 Hz. (i) Sketch the voltage and current waveform in the same axis by showing the important point. (ii) Determine instantaneous voltage when t = 8ms . (iii) Determine phase relationship between voltage and current waveform.
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