KS3: Magnetism Questions
Q4. The diagram shows a wire wrapped around a box to form a rectangular coil and circuit. The coil has two iron rods in it. The rods are parallel and touching. They are free to move.
(a) When the switch is closed, the two rods move apart.
(i) Explain why this happens.
3 marks
(ii) The switch is then opened to break the circuit. What, if anything, happens to the two iron rods?
1 mark
(b) One of the two iron rods is taken out and replaced with a brass rod.
The rods are parallel and touching.
What, if anything, will happen to the rods when the switch is closed?
Explain your answer.
2 marks
(Total 6 marks)