Available practice: 77 of 100 marks. Parts 1(b), 4(b)(i), 4(c), 6(a)(ii), 6(b)(ii), 7(a)(i), 7(a)(ii), 9(b)(i), 9(c), 10(b)(ii) await marking support. Scores cover available parts only.
A sinusoidal alternating potential difference (p.d.) from a supply is rectified using a single diode.
(a)(i)Determine the root-mean-square (r.m.s.) value of the supply potential difference before rectification.
Answer guidance
Determine Work it out from what you are given or from the figure, and show how you got there.
[2 marks]
A sinusoidal alternating potential difference from a supply is rectified using a single diode.
(a)(ii)State the type of rectification shown in Fig. 5.1.
Answer guidance
State A short answer. No explanation is needed, and adding one cannot earn extra marks.
[1 mark]
A sinusoidal alternating potential difference is rectified and smoothed using the circuit in Fig. 5.2. The capacitor has capacitance C of 85 μF and the resistor has resistance R. The effect of the capacitor and the resistor is to produce a smoothed output potential difference V_OUT. The difference between maximum and minimum values of V_OUT is 2.0 V.
(b)(i)On Fig. 5.1, draw a line to show V_OUT between times t = 1.0 ms and t = 5.0 ms.
[3 marks]
A sinusoidal alternating potential difference is rectified with a single diode and smoothed by a capacitor C = 85 μF in parallel with a resistor R, giving output V_OUT whose maximum and minimum values differ by 2.0 V.
(b)(ii)Determine the time, in s, for which the capacitor is discharging between times t = 1.0 ms and t = 5.0 ms.
Answer guidance
Determine Work it out from what you are given or from the figure, and show how you got there.
[1 mark]
(b)(iii)A rectified alternating p.d. is smoothed by a capacitor C = 85 μF in parallel with a resistor R; the difference between maximum and minimum values of V_OUT is 2.0 V, with peak value 8 V. Using your smoothed V_OUT line drawn on Fig. 5.1 and the discharging time found in (b)(ii), calculate the resistance R.
Answer guidance
Using You must use the thing it names. An answer that reaches the right value another way may not score.
[2 marks]
9702/04/SP/22Cambridge International AS & A Level Physics 9702 · Specimen 2022 · Paper 4 · Question 5
