Electricity and Magnetism Answers

) A uniform plane wave of 100 kHz travelling in free space strikes a large block of a
material having 4 , 9 and 0 ε = ε0 µ = µ0 σ = normal to the surface. If the incident
magnetic field vector is given by
10 cos( ) ˆ tesla 6 B = ωt −βy z
−
r
write the complete expressions for the incident, reflected, and transmitted field
vectors.

a stiff metal rod kept over two knife edges of length 1m. rod carries current of 16A. and rolls over rails without slipping due to uniform magnetic field of 0.5T perpendicular pointing downwards. rod starts from rest and attains speed of K/root5 when leaves rails. find value of K

A charge particle velocity in a plane perpendicular to a magnetic field describes a

In the cathode ray oscilloscope, when fast moving electrons strike the glass screen coated with zinc and sulphide they cause

A Wheatstone bridge ABCD (labelled in clockwise direction) with a galvanometer G joined to the junctions B and D. A cell E is connected across AC. Resistances of 15, 10, 4 and X ohms are inserted into the arms AB, BC, CD and DA respectively. The value of X is ------- ohms

A LRC series circuit has L=8.2mH, R=33ohm, and C=33uF. IF the ac source is 60-Hz and 5.0Vrms voltage, what is:
(a) the rms current in the circuit,
(b) the rms voltage of each element of the circuit
(c) the phase angle,
(d) the average power dissipated?

Long problem #1: Three wires carrying a 1.0-A current in the same direction. The wires are at the corners of an equilateral triangle of side s=1.0m. What is the magnetic field (magnitude and direction) at the center of the triangle?

Distinguish between piezoelectric and pyroelectric materials with an example of
each.

A wire with an alternating current flowing through it is placed in a magnetic field . This causes the wirw to oscillate with a frequency equal to the frequency of the current . This wire has a length L= 1.56 m . A mass of 221.0 g is hung on the end of the wire . The frequency of the current is initially set to f =52.5 hz . Three loops are observed in the wire at this frequency . 1. What is the wave velocity of the travelling wave ?
2. What is the mass per unit length for this wire?
3. What is the wavelength of the fundamental mode of vibration of the wire ?

Two objects are separated by a distance of 1.2 mm. The objects are initially neutral, and then each receive the same number of electrons, giving them the same charge. The force between the objects is now 24.0 pN. How many electrons did the two objects each receive?