A 4 e b e 2 c 2 e d e e 0 2 if 12 8 10 6 j of work is

(a) 4 E (b) E/ 2 (c) 2 E (d) E (e) 0
2. If 12 . 8 × 10 - 6 J of work is necessery to move 0.8 nC of charge from a positive plate to a negative plate, what is the potential
difference (voltage) between the plates?
(a) 16 V (b) 0.16 V (c) 6.25 V (d) 16 kV (e) 6.25 kV
3. In electrostatics (assuming V ( x → ∞ ) = 0) which of the following statements is not correct?
(a) Potential inside a spherical shell carrying a net charge on it is zero. (b) Potential difference between any points in a
conductor is zero. (c) Potential of a charge becomes zero only at infinite distance to the charge. (d) Potential is a scaler
quantity. (e) Potential due to discrete charges can be calculated from the superposition of the potentials of the individual
charges.
4. A positive charge q with mass m moves in the direction of electric field from point A to point B. What you can not say about
it?
(a) Its kinetic energy increases. (b) Its potential energy increases. (c) The work necessary to move this charge is negative.
(d) The work done on the charge is independent of the path. (e) The charge accelerates in the direction of the electric
field.
5.
In the figure, the electric field lines are shown for a system of two point charges Q
A
, and Q
B
. Which
of the following could represent the magnitudes and signs of Q
A
, and Q
B
? (take q to be a positive
quantity)
(a) Q
A
= - 3 q , Q
B
= +7 q (b) Q
A
= +7 q , Q
B
= - 3 q (c) Q
A
= +3 q , Q
B
= - 7 q (d) Q
A
= + q ,
Q
B
= - q (e) Q
A
= - 7 q , Q
B
= +3 q
6. Which of the following identifies the electromotive force (emf)?
I) Emf is the voltage developed by any source of electrical energy such as battery or dynamo.
II) Emf sources convert chemical, mechanical, and other forms of energy into electrical energy.
III) EMF is defined as the difference in electric potential between two points of a conducting wire when an electric current of
one ampere dissipates one watt of power between those points.
IV) Emf is the electric potential energy per unit charge.
(a) I (b) All is true (c) III and IV (d) I, II (e) I, II and III
7. Which of the following experiments should be performed if you want to measure the exact or very approximate value of the
electromotive force of a battery?
I) Measure the potential difference between the leads of the battery when the current of the circuit is zero.
II) Measure the potential difference between the leads of the battery when the net resistance which is series to the battery is
large enough.
III) Measure the potential difference between the leads of the battery when the net resistance which is series to the battery is
small enough.
(a) I and II (b) II and III (c) I (d) II (e) III
8. When the dielectric constant κ of the medium between the plates of a capacitor is increased, while the charges on the plates
kept constant, which of the following is/are true?
I) Potential difference between the plates increases. II) Electric field between the plates decreases. III) Potential energy of the
capacitor decreases.