Electric Circuits Answers

how many coulombs of charge are involved in a chemistry experiment in which 4 × 1024 electrons pass into a solution of silver chloride.

20 kHz audio signal is amplitude modulated over a 100 kHz carrier frequency. The peak amplitude of carrier wave is 10 V. If the modulation index is 0.8, find out the frequencies present in the modulated output. Also calculate the ratio of maximum and the minimum amplitude of the envelope of modulated signal.

The current in an a.c. circuit at any time t seconds is given by:
i = 5 sin(100πt − 0.432) A
Determine (a) the amplitude, frequency, periodic time and phase angle (in
degrees), (b) the value of current at t = 0, (c) the value of current at t =8ms,
(d) the time when the current is first a maximum, (e) the time when the current
first reaches 3A. Sketch one cycle of the waveform showing relevant points.

Three resistors are connected in series with one another. When a supply of 100V is applied to the circuit, current of 0.75A flows in it. The potential difference across one resistor is found to be 18.85V and the power dissipated by the second is 2.8W. Determine the value of the remaining resistance.

A 12µF capacitor is required to store 4J of energy. Find the p.d to which the capacitor must be charged

Two 6µF capacitance are connected in series with one having a capacitance of 12µF.Find the total equivalent circuit capacitance. What capacitance must be added in series to obtain a capacitance of 1.2µF.

A battery of e.m.f 20V and the internal resistance 0.2Ωsupplies a load taking 10A. Determine the p.d at the battery terminals of the load and the resistance of the load

Eight cells, each with an internal resistance of 0.2Ω and e.m.f of 2.2V are connected (a) in series (b) in parallel. Determine the e.m.f and the internal resistance of the batteries.

The temperature coefficient of resistance for carbon at 0oC is -0.0048/oC. What is the significance of the minus sign?
A carbon resistor has a resistance of 500Ω.Determine its resistance at 50oC

A business uses two 3kW fires an average of 20 hours each per week and six 150W lights for 30hours each per week. If the cost of electricity is 14.25p per unit, determine the weekly cost of electricity to the business.