1. Two identical charges q are separated by a distance r. The charges will repel with a force F.

If the distance between the charges is increased to 2r and both charges increased to 2q, the force will now be ...

  • A. F/4
  • B. F/2
  • C. F
  • D. 2F

2. An electronvolt is a unit of ...

  • A. work done
  • B. charge
  • C. voltage
  • D. current

3. Which of these diagrams correctly shows the electric field between positive and negative charges? (Only a limited number of lines are shown here).

Electric field lines x4

4. Electric field strength is defined as ...

  • A. the force per unit charge on a small positive test charge
  • B. the force per unit charge on a small negative test charge
  • C. the force per unit charge on a unit positive charge
  • D. the force per unit charge on a unit negative charge

5. Four metal spheres P,Q, R and S are arranged in a square as shown. Each one has a charge of q or -q or zero.

  
The electric field at a point in the centre of the square will be zero if ...
  • A. All charges are positive
  • B. P and Q are positive, R and S are negative
  • C. P and Q are positive, R and S have no charge
  • D. P is positive, Q R and S have no charge

6. A current flows in a metal wire when attached to a cell. Which of the following correctly describes the charge carriers in the wire and their movement?

  Charge carrier sign Moves round the circuit from
A + positive to negative
B - positive to negative
C + negative to positive
D - negative to positive

7-9: A small +2 mC charge is placed between two charged plates as shown. The plates have an electric field of 40 NC-1 between them. The apparatus is placed in a vacuum.

7. Which statement below best describes the acceleration of the charge is it moves?

  • A. Acceleration is zero, moves at constant velocity
  • B. Acceleration decreases as it moves downwards
  • C. Acceleration is constant
  • D. Acceleration increases as it moves downwards
8. The force on the charge due to the field will be ...
  • A. 20 N
  • B. 80 N
  • C. 0.02 N
  • D. 0.08 N

9. If the voltage between the 2 plates is 2kV, what is the work done in moving the charge from plate to plate?

  • A. 1 J
  • B. 4 J
  • C. 1 eV
  • D. 4 eV

10. Two metal wires A and B have identical currents flowing in them. Wire A has a smaller cross-sectional area than B. This means wire A ...

  • A. has charge carriers with a larger charge than B
  • B. is longer than B
  • C. has fewer charge carriers per unit volume than B
  • D. has a higher charge drift velocity than B