CSEC Physics · 1990 · Paper 2

32 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 marksState the amplitude and wavelength of the wave.
2. 1(a)(ii)3 marksCalculate the period and velocity of the wave.
3. 1(b)4 marksComplete the diagrams in Figure 2 to show the wavefronts after passing through (i) a narrow gap and (ii) a wide gap.
4. 1(c)(i)2 marksCalculate the frequency of the waves in air.
5. 1(c)(ii)5 marksCalculate the wavelength of the waves in the second medium and the angle of refraction.
6. 2(a)(i)2 marksGive the formula for calculating the efficiency of the engine.
7. 2(a)(ii)2 marksA car uses gasolene of energy content 40 MJ per litre. If its engine is 30% efficient, how much useful work does it do for every litre of gasolene consumed?
8. 2(a)(iii)3 marksThe car travels at constant speed against an average retarding force of 1200 N. How far can the car travel on 1 litre of gas?
9. 2(b)(i)2 marksState the principle on which the action of this machine is based.
10. 2(b)(ii)2 marksExplain how the principle is applied to obtain a force great enough to support a car.
11. 2(b)(iii)2 marksA force of 480 N is applied to piston A of area 0.01 m^2. What is the resulting pressure on the liquid?
12. 2(b)(iv)1 markWhat is the pressure on the large piston?
13. 2(b)(v)2 marksWhat is the total force exerted on the large piston if its area is 0.15 m^2?
14. 3(a)(i)2 marksState the composition of an alpha-particle.
15. 3(a)(ii)2 marksWhy was a vacuum necessary?
16. 3(a)(iii)1 markHow were the alpha-particles detected?
17. 3(a)(iv)2 marksExplain why most of the alpha-particles were able to pass through the foil undeviated.
18. 3(a)(v)2 marksName ONE scientist who had proposed another model of the atom just before this one, and briefly describe that model.
19. 3(b)4 marksGiven the nuclear reactions: 216_84 Po -> 212_82 Pb + X and 212_82 Pb -> 212_83 Bi + Y, name the emissions X and Y and write the symbols for them.
20. 3(c)3 marksThe activity of a sample of a radioactive element decreases to 1/4 of its original value in one hour. Calculate the half-life of the sample.
21. 4(a)(i)3 marksDraw diagrams to illustrate the difference between the structure of liquids and that of gases.
22. 4(a)(ii)3 marksExplain why gases are more easily compressed than liquids.
23. 4(b)(i)2 marksUsing the axes provided, sketch the graph expected when plotting the length of the air column against the kelvin temperature, T.
24. 4(b)(ii)2 marksState the 'law' which this experiment is used to investigate.
25. 4(b)(iii)1 markTheory suggests that the volume of the gas becomes zero at a certain temperature. What is the value of this temperature?
26. 4(c)5 marksA cylinder contains gas at 10 °C and 8.5 x 10^5 Pa. It is fitted with a valve which opens when the pressure is 1 x 10^6 Pa. At what temperature will the valve open?
27. 5(a)(i)2 marksState the essential difference between direct current and alternating current.
28. 5(a)(ii)3 marksA split-ring commutator is connected to the a.c. generator. On the axes provided, draw a graph to represent the output current assuming no other change in the circuit.
29. 5(a)(iii)4 marksThe commutator is removed and a p-n diode is placed in series with the a.c. generator. Distinguish between the p-type material and n-type material of which the diode is made.
30. 5(a)(iv)3 marksOn the axes provided, draw a graph of current against time to represent the output of the a.c. generator and diode.
31. 5(b)(i)3 marksCalculate the maximum permissible current in the resistor.
32. 5(b)(ii)1 markThe resistor is connected to an a.c. supply and an alternating current flows with a peak value equal to the maximum permissible current. Explain why the rate of energy conversion using a.c. will be less than that using…