PHYSICS · Multi-part · Fermi University Physics · Electricity, Magnetism & Electromagnetism · Electromagnetic induction and alternating-current circuits · Electromagnetic induction and alternating-current circuits
Electricity, Magnetism and Electromagnetism, Ch Alternating current: peak and rms values, the oscilloscope and rectification
Problem
A signal generator produces a sinusoidal voltage. Its output is displayed on an oscilloscope whose time base is set to 2.0ms per division and whose vertical sensitivity is set to 50V per division. On the screen one complete cycle occupies 5.0 horizontal divisions, and the crest of the trace lies 2.4 divisions above the zero line. The oscilloscope is ideal: it draws no current and it draws the waveform itself. The same output is then connected across a resistor of resistance 40Ω, whose resistance does not change with temperature.
((a)) Find the period and the frequency of the voltage.
((b)) Find the peak voltage and the root-mean-square voltage.
((c)) Find the mean power dissipated in the resistor.