Download Initial practice problems. + + - O O O 2m 5m What is the net force on

Initial practice problems.
+
O
+
O
O
2m
5m
What is the net force on each charge? Each unit charge is 1.602E-19C
What is the initial acceleration of each charge? (Me = 9.1E-31kg, Mp = 1.67E-27kg)
What happens to each acceleration after the initial instance?
O
X
2m
+
O
O
7m
What is the net force on each charge? Each unit charge is 1.602E-19C
What happens to each acceleration after the initial instance?
What is the Electric field strength at X?
1998E1. The small sphere A in the diagram above has a charge of 120  C. The large sphere B1 is a thin
shell of nonconducting material with a net charge that is uniformly distributed over its surface. Sphere B 1
has a mass of 0.025 kg, a radius of 0.05 m, and is suspended from an uncharged, nonconducting thread.
Sphere B1 is in equilibrium when the thread makes an angle = 20° with the vertical. The centers of the
spheres are at the same vertical height and are a horizontal distance of 1.5 m apart, as shown.
a. Calculate the charge on sphere B1.
b.
Suppose that sphere B1 is replaced by a second suspended sphere B2 that has the same mass, radius,
and charge, but that is conducting. Equilibrium is again established when sphere A is 1.5 m from
sphere B2 and their centers are at the same vertical height. State whether the equilibrium angle 2 will
be less than, equal to, or greater than 20°. Justify your answer.
1989E1. A negative charge - Q is uniformly distributed throughout the spherical volume of radius R shown
above. A positive point charge + Q is at the center of the sphere. Determine each of the following in terms
of the quantities given and fundamental constants.
a. The electric field E outside the sphere at a distance r > R from the center
b. The electric potential V outside the sphere at a distance r > R from the center
c. The electric field inside the sphere at a distance r < R from the center
d. The electric potential inside the sphere at a distance r < R from the center
The long, solid inner (insulating) core of the above object has a charge of +Q. The outer
shell has a charge of -2Q.
a)
b)
c)
d)
What are the volume & linear charge densities of the inner core?
Using Gauss Law, find the E field at any point r < a.
Using Gauss Law, find the E field at any point a < r < b.
Using Gauss Law, find the E field at any point r > b.
A charged plate has a charge
density of  = 1.5 µC/m2.
A small particle with a charge of
0.05 µC is placed 1m from the
plate.
What work is required to move
this charge halfway to the plate?
Let’s now move the particle VERY far away, so that the charged plate now appears to be
a point charge.
What work is required to move the small particle from 0.5m to infinity?