1.
1.  The potential at the surface of a solid conducting sphere is -8 Volts. All charges on the
sphere remain at rest. What is the potential at a point midway between the surface and center?
ANSWER IS -8 Volts.
2. An ideal parallel plate capacitor with a dielectric between the plates is charged and no charges
may exit or enter the capacitor plates, which are fixed in position.
2a. When the dielectric material is removed: 11. The voltage between the plates: a) increases b)
decreases c) remains the same d) more info is needed to determine *ANSWER = A
2b. The electric field: a) increases b) decreases c) remains the same d) more info is needed to
determine *ANSWER = A
2c. The potential energy: a) increases b) decreases c) remains the same d) more info is needed to
determine *ANSWER = A
3. Three identical lightbulbs are attached to a battery as shown. When switch S is opened so that
current does not flow through B, the brightness of A ________ by a factor of ________ a)
increases, 9/4 b) increases, 3/2 c) decreases, 9/16 d) decreases, 3/4 e) none of the above answers
are correct
30. Three identical lightbulbs are attached to a battery as shown. When switch S is opened so
that current does not flow through B, the brightness of A a) increases, 9/4 by a factor of
increases, 3/2 c) decreases, 9/16 tis inhal closed decreases, 3/4 e) none of the above answers are
correct 31. Find the power consumed by the 6 Ohm resistor. I2
Solution
1. Ans
While travelling radially in conductor field remains 0 so potential does not change and remains
same as that at surface.
2(a).Ans

2.
we know that potential across a capacitor is given by V = Q/C. When we will remove dielectric
C decreases so potential difference across capacitor increases.
2(b) Ans
As potential difference across capacitor increases and dielectric is removed so electric field given
by E=V/d increases.
2(c) Ans
We know that potential energy of capacitor having charge Q is given by U = (Q^2)/2C. So when
dielectric is removed C decreases so U increases.