CAPE Physics Unit 2 · 2016 · Paper 2

31 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)3 marksExplain how terminal potential difference, internal resistance and ideal source are related in a practical source of electromotive force (e.m.f.) such as an alkaline battery.
2. 1(a)(ii)2 marksState TWO qualitative practical observations which demonstrate the existence of internal resistance.
3. 1(b)(i)2 marksMeasurements of current, I_L, are recorded as the external resistance, R_L, is varied. Show that for this circuit, the relationship between the measured current, I_L, and the external resistance, R_L, can be…
4. 1(b)(ii)1 markComplete Table 1 by inserting the appropriate values in Column 3 for (I_L)^{-1} / \text{Amp}^{-1}.
5. 1(b)(iii)4 marksOn the grid provided in Figure 2, plot a graph of I_L^{-1} versus R_L and draw the best straight line through the points. Choose appropriate scales to ensure that the origin is included.
6. 1(b)(iv)1 markDetermine and record the intercept on the I_L^{-1} axis.
7. 1(b)(v)2 marksUse the intercept along with the equation given in (b)(i) to determine the internal resistance of the battery.
8. 2(a)6 marksDraw the circuit diagram and derive the expression for the gain of a non-inverting amplifier.
9. 2(b)2 marksThe circuit shown in Figure 3 is used in a tester for resistive transducers. Show that output voltage V_o and R_x are related by the equation V_o = 30\,000\, R_x^{-1} - 10, where R_3 = R_2 = 10\text{ k}\Omega,…
10. 2(c)(i)1 markComplete Table 2 by inserting the appropriate values in Column 2 for R_x^{-1} (10^{-3}).
11. 2(c)(ii)4 marksOn the grid provided in Figure 4, plot a graph of V_o versus R_x^{-1} and draw the best straight line through the points.
12. 2(d)2 marksUse your graph to determine the value of R_x which results in zero output voltage.
13. 3(a)4 marksX-rays are weakened by their passage through matter. Write the equation which quantifies this phenomenon, and state the meaning of EACH term in your equation.
14. 3(b)(i)3 marksComplete Table 3 by inserting the relevant values in Columns 3 and 4 (−\ln(I/I_0) or \ln(I/I_0)^{-1} and Total Thickness / mm).
15. 3(b)(ii)4 marksOn the grid provided in Figure 6, plot a graph of the natural log of attenuation, \ln(I/I_0) versus total thickness.
16. 3(b)(iii)3 marksUse your graph to determine the linear absorption coefficient of gold in \text{cm}^{-1} at the wavelength of the incident photons.
17. 3(b)(iv)1 markSuggest a reason why the linear absorption coefficient of a metal would decrease with decreasing wavelength of the incident beam.
18. 4(a)2 marksExplain the term 'drift velocity' when applied to the movement of electrons in a conductor.
19. 4(b)4 marksWrite the meaning of EACH variable in the equation I = nevA and state the unit in EACH case.
20. 4(c)(i)5 marksCalculate the drift velocity of electrons in the wire in millimetres per second.
21. 4(c)(ii)2 marksSuggest a reason why this value is so small compared to the other values of electron velocity commonly encountered in physics.
22. 4(c)(iii)2 marksWould the drift velocity in a semiconductor material of similar dimensions carrying the same current be greater than that of the conductor in (c)(i)? State a reason for your answer.
23. 5(a)(i)6 marksWith the aid of a diagram, explain the operation of a simple half-wave rectifier circuit which employs a junction diode. Indicate the polarity of the output voltage on the diagram.
24. 5(a)(ii)1 markSketch the output voltage when the input is a sine wave.
25. 5(b)(i)1 markDetermine the peak voltage.
26. 5(b)(ii)2 marksDetermine the frequency.
27. 5(b)(iii)2 marksDetermine the root mean square (rms) voltage.
28. 5(c)3 marksDraw a labelled sketch (do not plot) showing the correct values of amplitude and period for two cycles of the output voltage when this waveform is applied to a simple half-wave rectifier circuit.
29. 6(a)8 marksDescribe the Geiger–Marsden experiment and discuss the evidence it provides for the nuclear model of the atom.
30. 6(b)2 marksCobalt-60 is obtained by irradiating natural Cobalt-59 with fast neutrons, then emits a beta particle to form nickel. (Atomic numbers: \text{Co} - 27, \text{Ni} - 28). Complete the nuclear equations for this…
31. 6(c)5 marksCobalt-60 has a half-life of 5.27 years. Beginning with an initial sample of 200 grams of pure Co-60, determine how many grams of nickel would be found after three years. Neglect the mass equivalence of the energy in…