Electricity and Magnetism Answers

A typical capacitor in a memory cell have a capacitance of 3 x 10-14 F. If the voltage across the capacitor is 0.5 V, what is the number of electrons that must move to the capacitor to charge it? 

Two point charges are placed as follows: charge q1 = -1.50 nC is at y = +6.00 m and charge q2 = +3.20 nC is at the origin. What is the total force (magnitude and direction) exerted by these two charges on a negative point charge q3 = -5.00 nC located at (2.00 m, -4.00 m)? 

A ball of mass m1=4kg and a block of mass m2=10kg

are attached by a lightweight cord that passes

over a frictionless pulley of negligible mass, as in figure below. The block lies on a frictionless incline of

angle θ=48 degrees. Find the magnitude of the acceleration of the two objects and the tension in the cord.

In a tuned circuit,if a capacitor is added only to the secondary coil, derive the current and voltage across the capacitor in the resultant circuit.

Two point charge Q1 and Q2 are 3m apart, and their combined charge is 20micro coulumb.

(a) if one repels the other with a force of 0.075N, what are the two charges?

(b) if one attract the other with a force of 0.525N, what are the magnitude of the charges?

In the milikan experiment,and oil drop carries four changes and has a mass of 1.8*10^-12g.it is held almost at rest between two horizontal charged plates 1.8cm apart. What voltage must there be between the two charged plates?

four equal charge, Q = 2 microcoulomb,are located at the corners of a square that is 0.50m on a side. What is the potential energy of the array?

What is the formula to get the time interval

A soccer goal, found in a city park, is made of tubing that supports an

odd-shade hanging net behind the goal, but has a rectangular opening

in front. The height of the opening is 2.8m and the width is 3.5m.

If a uniform electric field, with 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 electric field enters the goal at 60 degrees angle

to the plane of the front of the goal. In both cases, assume that there is

no charge found inside the goal itself.

Find the total electrostatic energy of a uniformly charged sphere of total charge q and radius R