Electricity and Magnetism Answers

The back e.m.f induced in coil when electric charges from 1A to zero in millisecond is 4 volt. Find the self induction n(L) of coil.

A proton beam is moving vertically downward. It passes through a magnetic field directed horizontally from south to north. The beam is directed toward:

1- east 2- west 3- north 4- south

The north pole is away from a metallic ring lying horizontally. The direction of current is:

1- anti clock wise 2- clock wise

3- no current induced

If a vector field A(x,y,z)=xz3ex - 2x2yzey+2yz4ez , calculate the divergence Ñ·A at point M(1,-1,-1).

1) If a scalar field φ(x,y,z)=3x2y-y3z2, calculate the gradient Ñφ at point M(1,-2,1).

Define and explain hall's effect and hall's effect in semi-conductor. Derive the magnitude of hall's voltage. What is the use of hall's effect?

State and explain Lenz's law the lenz's law is also a statement of law of conservation of energy. Explain, does the lenz's law violate the principle of law of conservation of energy.

What are Maxwell’s four integral equations

State and explain the phenomenon of electromagnetic induction and also explain various methods of changing the magnetic flux through a loop state and explain faraday's law of electromagnetic induction.

What do you mean by induced e.m.f and induced current?