2023 · Specimen · 5054/02 | Q7

0/45parts marked · 0 of 80 marks

Question (7 of 10)8 marks · Practise this topic →

Options

You may use a calculator. You should show all your working and use appropriate units. Take the weight of 1.0 kg to be 9.8 N (acceleration of free fall = 9.8 m/s²).

(a)(i)

Fig. 7.1 shows a horizontal, current-carrying wire PQ in the gap between the poles of a permanent magnet.

Fig. 7.1: wire PQ between the N and S poles of a permanent magnet, with the current arrow from P to Q.

There is a magnetic field in the gap between the N pole and the S pole.

The current in PQ is from left to right.

Describe the effect of the magnetic field on PQ.

Answer guidance

State A short answer. No explanation is needed, and adding one cannot earn extra marks.

[2 marks]

(a)(ii)

State the effect on PQ of increasing the strength of the magnetic field in the gap.

Answer guidance

State A short answer. No explanation is needed, and adding one cannot earn extra marks.

[1 mark]

(b)(i)

Fig. 7.2 shows part of a torch. The torch does not contain a battery.

Fig. 7.2: a coil and a magnet labelled N and S, with arrows indicating motion through the coil.

The torch is shaken and this causes the magnet to move backwards and forwards through the coil.

Explain why an electromotive force (e.m.f.) is induced across the coil when the magnet moves.

Answer guidance

Explain Give reasons, not just what happens. Each distinct reason is usually worth a mark.

[2 marks]

(b)(ii)

State one way to increase the e.m.f. induced.

Answer guidance

State A short answer. No explanation is needed, and adding one cannot earn extra marks.

[1 mark]

(b)(iii)

As the magnet moves into the coil, the induced e.m.f. produces a current in the coil.

Explain how this opposes the motion of the magnet.

Answer guidance

Explain Give reasons, not just what happens. Each distinct reason is usually worth a mark.

[2 marks]

5054/02/SP/23Cambridge O Level Physics 5054 · Specimen 2023 · Paper 2 · Question 7