Electricity and Magnetism Answers

An alternating pd 220V amplitude and frequncy 50Hz is applied to a series circuit containing R=400 ohms, L=0.35H and C= 18 micro farad (a) what is Z? (b) what is the current amplitude ,is it lagging the supply pd (c) what is the power factor?

A radio station set is returned from the 108MHz to 90.5MHZ station using a variable capacitor. By what factor is the capacitance change?

Three charged particles are placed at the corners of an equilateral triangle of side 1.20 m. The charges are Q1= 6.7 μC, Q2 = -9.4 μC, Q3= -4.9 μC .

1. Calculate the magnitude of the net force on particle 2 due to the other two.
2. Calculate the magnitude of the net force on particle 3 due to the other two.
3. Calculate the direction of the net force on particle 3 due to the other two.

A torold ‏Has 750 turns the radius of the circle through the centre of its winding is 5 cm what current in the winding will produce in magnetic field of 1.8x10^-3 tangent to this central circle

Find the electric flux through the surfaces 1 to 5 in the figure below. Height of the object is 2.0 m Width is 4.0 m. The object is angled at 30 degrees with E equalling 400 N/C

a current coil of cire 10cm in diameter has 18turns and carries a current of 8a .the coil is inserted into a field of magnetic induction 1.2t what is the maximum torque on the coil?

A circular coil of wire 10cm in diameter has 18 turns and carries a current of 8A. The coil is inserted into a field of magnetic induction 1.2T (a) what is the maximum torque on the coil? (b) what is the dipole moment of the coil?

Are circular coil of radius 40mm is found to produce a field 12.1×10^-6 T at a point 30mm along its axis.(a) what is the electromagnetic moment? (b) what maximum torque could it experience in a uniform magnetic field of 3.0×10^-3T.

A full wave rectifier circuit gives a reading 1.5A on a moving coil instrument. What are the peak and rms values of the current.

A resistive florescent bulb rated at 40w is designed to carry a current of 2.5A. (a) what is it's resistance? A choke is connected in series with the lamp to enable it be energiesed by the 240V,50Hz mains. (b)What is the inductance to the choke (c) A capacitor in series with a resistor is now connected in parallel to the lamp and choke so that their current lead compensates for the lag introduced by the inductor.find the value of C for this resonant circuit.