1. Two identical charges q are seperated 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


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 strength between these two charges?


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


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.


5. 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 


A 2 mC charge is held between two charged plates. The plates have an electric field of 40 'units'^{} between them.


7. The unit of electric field strength E is
 A. NC
 B. NV
 C. NC^{1}
 D. NV^{1}



8. The force on the charge due to the field will be
 A. 20N
 B. 80N
 C. 0.02N
 D. 0.08N


9. If the voltage between the 2 plates is 2kV, the work done in moving the charge from plate to plate is
 A. 1J
 B. 4J
 C. 1eV
 D. 4eV


10. Two metal wires A and B have identical currents flowing in them . Wire A has a smaller crosssectional area than B. This means wire A must also
 A. have charge carriers with a larger charge than B
 B. be longer than B
 C. have fewer charge carriers per unit volume than B
 D. have a higher charge drift velocity than B



