1a
2 marks
2 marksDefine electric field strength.
1b4 marks
4 marksFig. 1.1 shows the electric field lines between two charged spheres, A and B.
Fig. 1.1
Using Fig. 1.1, state and explain which of the spheres, A or B, has
(i)
a negative charge
[2]
(ii)
a greater magnitude of charge.
[2]
1c2 marks
2 marksState the formula for the electric field strength 
at the surface of the sphere and state the meaning of any other symbols used.
1d4 marks
4 marksThe field strength at the surface of sphere A is 2.6 × 103 V cm–1, and the field strength at the surface of sphere B is 1.3 × 103 V cm–1.
The magnitude of the charge stored on the surface of sphere B is 7.5 µC.
(i)
Show that the radius of sphere B is about 7 cm.
[2]
(ii)
Calculate the magnitude of the charge stored on the surface of sphere A.
Assume both spheres have an equal radius.
Assume both spheres have an equal radius.
[2]
Did this page help you?
, the electric field strength decreases to 10.8 kV m–1.
).