Theory: answer each printed part. For drawings, upload a clear photo of your sketch on the supplied figure; show working and units for calculations.
Fig. 9.1 shows a simple a.c. generator.
(a)Explain why there is a voltage induced in the coil when the coil is turned.
Answer guidance
Explain Give reasons, not just what happens. Each distinct reason is usually worth a mark.
[2 marks]
(b)In Fig. 9.1 the coil is horizontal, with side AB on the left. The output voltage is +6.0 V. On Fig. 9.2 draw a line from each of the shaded boxes to one of the circled voltages to show the voltage output when the coil is in different positions. One line has been drawn for you.
[2 marks]
(c)(i)Both an a.c. generator and a d.c. motor contain a coil and brushes. Fig. 9.1 shows how the brushes are connected to the coil in an a.c. generator. Draw a diagram to show how the brushes are connected to the coil in a d.c. motor.
Answer guidance
Draw Accuracy is being marked. Use the figure and be precise about position and labels.
[2 marks]
(c)(ii)Both an a.c. generator and a d.c. motor contain a coil and brushes. State why there are forces on the sides of the coil in a d.c. motor.
Answer guidance
State A short answer. No explanation is needed, and adding one cannot earn extra marks.
[1 mark]
5054/21/M/J/23Cambridge O Level Physics 5054 · May/June 2023 · Paper 2 variant 1 · Question 9