Fig. 7.1 shows an alternating current (a.c.) power supply connected to a transformer. [Figure 7.1]

1. (a)Explain how an alternating current in the primary coil produces an alternating output voltage.[3]
2. (b)(i)A student uses a voltmeter set on a 0-10V range to measure the input and output voltages. She obtains the values shown in Table 7.1. [Table 7.1] Suggest why no output voltage reading is obtained with this voltmeter when the input voltage is 6.4V.[1]
3. (b)(ii)The number of turns on the primary coil is 48. Calculate the number of turns on the secondary coil. number of turns = ....................................................[2]
4. (c)(i)The student uses an oscilloscope to display an alternating output voltage from the transformer. Fig. 7.2 shows the front of the oscilloscope before it is connected to the transformer. [Figure 7.2] When the oscilloscope is connected to the output of the transformer, a trace representing the alternating output voltage is displayed on the screen. On Fig. 7.2, draw a trace representing an alternating output voltage on the screen.[1]
5. (c)(ii)Describe how to use the trace to measure the maximum value of the output voltage.[2]

This question uses a diagram from the original paper, which isn't shown here. Open the full paper from the past papers archive to see it.