Electricity and Magnetism Answers

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?

You hold a spherical salad bowl 90 cm in front of your face with the bottom of the bowl
facing you. The salad bowl is made of polished metal with a 35-cm radius of curvature. (a)
Where is the image of your 2.0-cm-tall nose located? (b) What are the image’s size, orientation,
and nature (real or virtual)?

A circular iron ring has a mean circumference of 1.5 m and cross-sectional area of 0.01 m
2
. A saw cut of 4 mm wide is made in the ring. Calculate themagnetizing current required to produce a flux of 0.8 mwb in the gap if thering is wound with a coil of 175 turns. Assume relative permeability of iron as400 and leakage factor 1.25

The unit of permitivity is

Electric field is which type of physical quantity?

How does a wave group get constituted ?
Obtain an expression for the velocity of a
wave group. What is the relation connecting
the group and phase velocities ?

Two mateeial Ge and Al are cooled from 300k to 600k. What will be its effect on their resistivity

A proton moves perpendicularly to a magnetic field that has a magnitude of 4.20*10^-2=T What is the speed of the particle if magnitude of magnetic force on it is 2.40*10^-14N

F'(r) = (2pxy)i+(3qyz^2-py^2)j-(qz^3)k
Where p and q are constants. (i,j,k are the vectors, couldn't seem to do ˆ above them)

Show this is a solenoidal field.

In an experiment, 295 mg of copper is deposited when a current of 500 mA passes for 30 minutes. Find the electrochemical equivalent of copper?