Electricity and Magnetism Answers

• To take Maxwell’s equations in differential form as example:

1. Please briefly describe the physical significance of Gauss’s law for electrical fields.

2. Please briefly describe the physical significance of Faraday’s law of electromagnetic induction.

Maxwell’s equations in differential form are composed of four equations

as follows:

1. Gauss’s law for electrical fields....................;                               
2. Faraday’s law of electromagnetic induction................;
3. Gauss’s law for magnetic fields..............; 4. Ampere's circuital law.........;

Please briefly describe the physical significance of Gauss’s law for electrical fields.

Please briefly describe the physical significance of Faraday’s law of electromagnetic induction.

An electron and a proton move in circular orbits in a plane perpendicular to a uniform magnetic 

field 𝐵⃗ . Find the ratio of the radii of their circular orbits when the electron and the proton have (a) 

the same momentum and (b) the same kinetic energy. (c) Sketch the path taken by the electron and 

proton when the magnetic field is directed into the board.

. A soccer goal, found is a city park, is made up of tubing that supports 

an odd-shaped hanging net behind the goal, but has a rectangular 

opening in front. The height of the opening is 2.5m and the width is 

3.2m. If a uniform E-field, with a magnitude of 0.1N/C, passes through 

the goal from the front to the back, entering at 90 degrees to the plane 

of the goal opening, what is the flux through the net? Also, find the flux 

through the net if the E-field enters the goal at 60 degrees angle to the 

plane of the front goal. In both cases, assume that there no charge 

found inside the goal itself. CR (10)

a bus travels with an average velocity of 60kmh^1.how long does it take to cover a distance of 500km

If in the process of rubbing the lenses, 6.2*1010 electrons were transferred, what is the charge of the lenses and the nylon cloth? what is the change in their masses?

Two small spheres , with a charge of Q1 on the other sphere and a charge Q2 on the other sphere ,have a distance r between their centers so thata they exert a force F on each other.What will happen to the force force F between them if one of the charges is doubles?

If bothe the charges are doubled?

3. Inside an isolated sphere of radius R the electric charge Q is evenly distributed. After a

redistribution, the density of the load becomes:

ρ (r) = k (2 * r / R-r ^ 3 / R ^ 3)

Determine the value of the constant k.