CAPE Physics Unit 2 · 2002 · Paper 2

53 questions and parts from this paper. Open one to see it in full, then practise it on Quelpr and get it marked against the mark scheme.

1. 1(a)2 marksDraw a circuit diagram showing how to connect the cell, ammeter, voltmeter, and variable resistor to measure the internal resistance and e.m.f. of the cell.
2. 1(b)(i)1 markDraw the best straight line through the points plotted on Figure 1.
3. 1(b)(ii)a)2 marksFrom the graph in Figure 1, deduce the value of the internal resistance of the cell.
4. 1(b)(ii)b)1 markFrom the graph in Figure 1, deduce the e.m.f. of the cell.
5. 1(iii)3 marksHence, calculate the current through the circuit and the potential difference across the terminals of the cell when connected to a 3 Ω resistor.
6. 1(iv)1 markState what instrument could be used instead of the voltmeter to obtain more accurate voltage readings.
7. 2(a)(i)4 marksDraw a circuit diagram to show how to achieve full-wave rectification using four diodes.
8. 2(a)(ii)2 marksExplain how this circuit can be modified to provide half-wave rectification.
9. 2(b)(i)2 marksBriefly describe what happens to D1 and D2 as 1 cycle of voltage Vs is applied to the circuit.
10. 2(b)(ii)1 markSketch the waveform expected on the cathode ray oscilloscope (c.r.o.) across the output Vo.
11. 2(b)(iii)1 markCompare the output waveforms from 2(a)(i) and 2(b)(i).
12. 3(a)(i)3 marksUse the graph grid provided on page 8 to plot a graph of current versus voltage for the metal.
13. 3(a)(ii)1 markFrom the plotted graph, record the stopping potential for the metal.
14. 4(c)(i)2 marksCalculate the induced e.m.f. in the loop.
15. 4(c)(ii)3 marksCalculate the induced current in the loop.
16. 4(d)4 marksThe magnetic field is held at a constant value B, and the coil is rotated at 10 rev s^-1 with its plane initially parallel to B. A voltmeter connected via rotating contacts reads a peak value of 13.0 mV. Find the…
17. 5(a)(i)3 marksDerive an expression for the equivalent resistance of THREE resistors connected in parallel.
18. 5(a)(ii)2 marksDistinguish between the electromotive force of a cell and the terminal potential difference across a cell.
19. 5(b)3 marksA parallel combination of rheostats R1 and R2 is used for current control (Figure 7), where the total resistance of R1 is 25 times that of R2. Describe the procedure to adjust the circuit current I to a desired value.
20. 5(c)(i)4 marksCalculate the resistance of the voltmeter.
21. 5(c)(ii)5 marksCalculate the voltmeter reading when connected across A'B' in Figure 8(ii).
22. 5(c)(iii)3 marksState what the results suggest concerning the use of voltmeters in electrical circuits.
23. 6(a)(i)3 marksState THREE ideal properties of operational amplifiers (Op-Amps).
24. 6(a)(ii)3 marksFor the Op-Amp circuit shown in Figure 8, show that the output voltage is given by Vo = - (Rf / R1) V1 - (Rf / R2) V2.
25. 6(a)(iii)1 markSuggest a practical use for this summing amplifier circuit.
26. 6(b)(i)1 markWrite an equation relating the r.m.s. value and the peak value of an alternating current.
27. 6(b)(ii)3 marksA car battery-charger operates from a 120 V r.m.s. a.c. line and supplies 10 A d.c. at 14 V. If it is 80% efficient, calculate the current drawn from the a.c. line.
28. 6(b)(iii)3 marksIf electricity costs 16 cents/kWh, calculate the cost of operating the charger for 10 hours.
29. 6(c)(i)2 marksCalculate the r.m.s. current supplied to the consumer.
30. 6(c)(ii)2 marksDetermine the turns ratio Ns / Np for EACH transformer, S and T.
31. 6(c)(iii)2 marksCalculate the current in the transmission supply cable.
32. 7(a)5 marksExplain the shape of the gain-frequency response curve for an operational amplifier shown in Figure 10.
33. 7(b)(i)2 marksDistinguish between an analogue circuit and a digital circuit.
34. 7(b)(ii)1 markWrite the truth table for a NAND gate.
35. 7(b)(iii)3 marksDetermine the output waveform X for the NAND gate circuit shown in Figure 11 when inputs A and B are applied.
36. 7(c)(i)4 marksA room lamp is controlled by switches at the front and back doors: the lamp is ON if exactly one switch is ON, and OFF if both are OFF or both are ON. Draw a logic circuit to meet these requirements, showing the…
37. 7(c)(ii)3 marksUsing two OR gates, one AND gate, and three INVERTERs, show how to design a half adder circuit.
38. 7(c)(iii)2 marksDraw the resulting truth table for the sum and carry outputs of the half adder.
39. 8(a)(i)2 marksIn the radioactive decay law N = N0 e^(-λt), explain the meaning of EACH symbol.
40. 8(a)(ii)3 marksShow that N = N0 e^(-λt) can be written as N = N0 2^(-t / t_(1/2)), where t_(1/2) is the half-life.
41. 8(a)(iii)1 markExplain what isotopes are.
42. 8(a)(iv)2 marksExplain why carbon dating is unable to provide accurate age estimates for very old materials.
43. 8(b)6 marksA nuclide 238_92 U decays to 214_82 X via FIVE successive decays, each emitting either an alpha particle or a beta particle. Determine the value of mass number A.
44. 8(c)(i)4 marksCalculate how long it will take for the number of atoms of each isotope to become equal.
45. 8(c)(ii)2 marksSketch the decay curves for the two isotopes on the same axes.
46. 9(a)(i)2 marksDistinguish between nuclear fusion and nuclear fission.
47. 9(a)(ii)4 marksSketch a graph of binding energy per nucleon versus mass number, and explain how nuclear fission and fusion can be understood from the shape of the curve.
48. 9(b)(i)1 markExplain what is meant by mass defect.
49. 9(b)(ii)1 markExplain what is meant by binding energy of an atomic nucleus.
50. 9(c)6 marksThe nitrogen nucleus 15_7 N has a mass of 15.9963 u. Calculate the binding energy per nucleon of this nucleus.
51. 9(d)2 marksShow that a uranium-238 nucleus can disintegrate spontaneously with the emission of an alpha particle.
52. 9(e)(i)2 marksAssuming the uranium-238 nucleus was at rest before disintegration, calculate the total energy released in the disintegration.
53. 9(e)(ii)2 marksCalculate the kinetic energy of the emitted alpha particle.