CAPE Physics Unit 2 · 2001 · Paper 2

47 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)(i)2 marksOutline TWO precautions to improve the accuracy of the results.
2. 1(a)(ii)2 marksConstruct a suitable circuit diagram that could be used for this investigation.
3. 1(b)(i)3 marksUse the graph on page 5 to calculate the value of the constant A.
4. 1(b)(ii)3 marksCalculate the value of R_0 using a value for T of 333 K.
5. 2(a)3 marksDraw a circuit diagram to show how the operational amplifier could be used over a wider range of frequencies at a reduced gain.
6. 2(b)1 markState what feature allows the gain to be reduced.
7. 2(c)2 marksState what adjustment can be made to your circuit to lower the gain.
8. 2(d)2 marksState what effect(s) this would have on the amplifier.
9. 2(e)2 marksGiven that the closed loop gain is related to the open loop gain by A = A_0 / (1 + β A_0), where β is a negative fraction of output fed back to the input, calculate the value of β when A_0 = 10^5 and A = 10^2.
10. 3(a)(i)3 marksDescribe an experiment that can be performed in the laboratory to show the existence of β-particles.
11. 3(a)(ii)1 markExplain how to determine the sign of the charge of a β-particle.
12. 3(b)(i)5 marksElectrons are accelerated through a potential difference of 40 000 V before striking a target to produce X-rays. Calculate the minimum cut-off wavelength λ_0 produced.
13. 3(b)(ii)1 markState what change occurs in λ_0 if the accelerating potential difference is doubled.
14. 4(a)(i)4 marksDefine the volt, and use this definition to derive the relationship P = IV.
15. 4(a)(ii)6 marksAn electric heater element has resistance 7.90 Ω and an applied potential difference of 115 V. Determine the current in the wire and the power used by the heater. State what happens to the power if the potential…
16. 4(b)(i)3 marksState Kirchhoff's laws.
17. 4(b)(ii)7 marksIn Figure 1, a battery of e.m.f. 12.0 V and internal resistance 0.011 Ω powers a lamp of resistance 1.20 Ω, while being charged by a charger of e.m.f. 14.0 V and internal resistance 0.10 Ω. Calculate the currents I_L,…
18. 5(a)8 marksGive a detailed explanation of the origin of the Hall effect and define the Hall potential difference. Include a diagram clearly showing relevant vector quantities for a specimen in which electron conduction…
19. 5(b)(i)7 marksA p.d. of 8.75 mV is produced across its edges. Given that the magnitude of charge of each carrier is 1.6 × 10^(-19) C, calculate the number of charge carriers per unit volume, explaining your calculation.
20. 5(b)(ii)5 marksDeduce what type of material is best suited for a large Hall potential difference, and describe how the magnitude of the magnetic field and the thickness of the material affect the Hall potential difference.
21. 6(a)1 markWrite down the truth table for the Exclusive-OR (EX-OR) gate.
22. 6(b)(i)3 marksConstruct the truth table for the circuit shown in Figure 3.
23. 6(b)(ii)2 marksDescribe in words the logic function of the circuit shown in Figure 3.
24. 6(c)(i)2 marksUsing the EX-OR gate, draw a circuit of a half-adder showing clearly the inputs A and B and the outputs of the circuit.
25. 6(c)(ii)3 marksShow how the full-adder circuit can be implemented from two half-adder circuits.
26. 6(d)9 marksShow the block diagram and explain the operation for the addition of the two binary numbers 110 and 101 using adders.
27. 7(a)3 marksGive THREE properties of an ideal operational amplifier.
28. 7(b)5 marksFor the non-inverting amplifier shown in Figure 4, show that the closed loop voltage gain, A, is given by A = 1 + R_f / R_i.
29. 7(c)(i)1 markDetermine the closed loop gain.
30. 7(c)(ii)2 marksWhen this circuit is used it saturates at ±13 V. If saturation is to be avoided, calculate the maximum input voltage that can be used.
31. 7(c)(iii)2 marksDetermine the output voltage for a sinusoidal signal of peak input voltage 3 V.
32. 7(c)(iv)2 marksSketch the resulting output signal when the peak input voltage is 3 V.
33. 7(d)5 marksDesign an op-amp summing circuit to combine three signals V_1, V_2, and V_3 to produce V_0 = -V_1 - 4V_2 - 12V_3, such that the input resistance at the inputs is not less than 10 kΩ and all resistor values are less than…
34. 8(a)(i)4 marksDiscuss the physical process described by E_2 - E_1 = hf and state what EACH term represents.
35. 8(a)(ii)4 marksExplain what is meant by 'work function'. State the energy transformation that takes place when light is incident on a surface causing electron emission, and give an equation relating the relevant quantities.
36. 8(b)(i)3 marksDetermine the energy of each photon emitted.
37. 8(b)(ii)4 marksDetermine the number of photons emitted per second.
38. 8(c)5 marksIf the light is incident on a surface with work function 2.05 eV, state whether electrons will be emitted, and if so, calculate their maximum kinetic energy. (1 eV = 1.6 × 10^(-19) J)
39. 9(a)(i)2 marksExplain the meaning of the statement that ^14_6C has a half-life of 55 s.
40. 9(a)(ii)2 marksExplain the meaning of the statement that ^14_6C has a decay-constant of 1.25 × 10^(-2) s^(-1).
41. 9(a)(iii)3 marksExplain the meaning of the statement that the radioactive decay of ^14_6C is a random and spontaneous process.
42. 9(b)1 markName ONE external condition that does not affect radioactive decay.
43. 9(c)(i)3 marksDetermine the number of nuclei present initially.
44. 9(c)(ii)3 marksDetermine the decay constant from the data provided.
45. 9(c)(iii)2 marksDetermine the half-life of the sample.
46. 9(c)(iv)2 marksDetermine the activity after 8 hours.
47. 9(c)(v)2 marksDetermine the number of radioactive nuclei remaining after 8 hours.