Q1. (a) State what is produced when an electron and a positron annihilate each other (1)

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1 Q. (a) State what is produced when an electron and a positron annihilate each other. () (b) (i) Explain why mass is not necessarily conserved when particles interact or decay () (ii) Momentum is conserved in all particle interactions. Name the three other conservation laws that are obeyed in all nuclear interactions (3) (Total 5 marks) Q2. The work function of sodium is 2.28 e V. (a) State what is meant by the term work function. (2) (b) alculate the threshold frequency for sodium. threshold frequency... Hz (3) (Total 5 marks) Page of 2

2 Q3. Earthquakes produce transverse and longitudinal seismic waves that travel through rock. The diagram below shows the displacement of the particles of rock at a given instant, for different positions along a transverse wave. (a) State the phase difference between (i) points and on the wave... (ii) points and on the wave... (2) (b) escribe the motion of the rock particle at point during the passage of the next complete cycle. (2) (c) scientist detects a seismic wave that is polarised. State and explain what the scientist can deduce from this information. (2) (d) The frequency of the seismic wave is measured to be 6.0 Hz. (i) efine the frequency of a progressive wave () Page 2 of 2

3 (ii) alculate the wavelength of the wave if its speed is m s. wavelength... m (2) (Total 9 marks) Q4. The motion of a long jumper during a jump is similar to that of a projectile moving under gravity. The figure below shows the path of an athlete above the ground during a long jump from half-way through the jump at position, to position at which contact is made with sand on the ground. The athlete is travelling horizontally at. (a) uring this part of the jump, the centre of mass of the athlete falls.2 m. (i) alculate the time between positions and. time... s (3) Page 3 of 2

4 (ii) The athlete is moving horizontally at with a velocity of 8.5 m s. ssume there is no air resistance. alculate the horizontal displacement of the centre of mass from to. horizontal displacement... m (2) (b) (i) The athlete in the image above slides horizontally through the sand a distance of 0.35 m before stopping. alculate the time taken for the athlete to stop. ssume the horizontal component of the resistive force from the sand is constant. time... s (2) (ii) The athlete has a mass of 75 kg. alculate the horizontal component of the resistive force from the sand. horizontal component of resistive force... N (3) (Total 0 marks) Q5. The cells in the circuit shown in the figure below have zero internal resistance. urrents are in the directions shown by the arrows. R = 0 0Ω R 2 = 0Ω R is a variable resistor with a resistance that varies between 0 and 0 Ω. (a) Write down the relationship between currents I, I 2 and I 3. () Page 4 of 2

5 (b) R is adjusted until it has a value of 0 Ω. State the potential difference across R 3. potential difference =... V () (c) etermine the current I 2. current =... J (2) (d) State and explain what happens to the potential difference across R 2 as the resistance of R is gradually increased from zero. (3) (Total 7 marks) Q6. The wire in an electric heater has a resistance of 75 Ω. It is 9.5 m long and has a crosssectional area of m 2. alculate the resistivity of the material from which the wire is made. Give an appropriate unit for your answer. resistivity... (Total 3 marks) Page 5 of 2

6 Q7. What are the numbers of hadrons, baryons and mesons in an atom of 7 3 Li? hadrons baryons mesons Q8. Electron capture can be represented by the following equation. p + e - X + Y Which row correctly identifies X and Y? X Y p K - e - e + n V e n π 0 Q9. In a photoelectric experiment, light is incident on the metal surface of a photocell. Increasing the intensity of the illumination at the surface leads to an increase in the work function minimum frequency at which electrons are emitted current through the photocell speed of the electrons Page 6 of 2

7 Q0. The diagram drawn to scale shows some of the energy levels of an atom. Transition P results in the emission of a photon of wavelength m. Which one of the transitions,,, or could result in the emission of a photon of wavelength m? Q. The cell in the circuit has an emf of 2.0 V. When the variable resistor has a resistance of 4.0 Ω, the potential difference (pd) across the terminals of the cell is.0 V. What is the pd across the terminals of the cell when the resistance of the variable resistor is 2 Ω? 0.25 V 0.75 V.33 V.50 V Page 7 of 2

8 Q2..5 m length of wire has a cross-sectional area m 2. When the potential difference across its ends is 0.20 V, it carries a current of The resistivity of the material from which the wire is made is Ω m Ω m. 0 6 Ω m Ω m Q3. In the circuit shown in the diagram the cell has negligible internal resistance. What happens to the reading of both meters when the resistance of R is decreased? Reading of ammeter Reading of voltmeter increases increases increases decreases decreases increases unchanged decreases Page 8 of 2

9 Q4. In the circuit shown, V is a voltmeter with a very high resistance. The internal resistance of the cell, r, is equal to the external resistance in the circuit. external resistance Which of the following is not equal to the emf of the cell? the reading of the voltmeter when the Switch S is open the chemical energy changed to electrical energy when unit charge passes through the cell twice the reading of the voltmeter when the switch S is closed the electrical energy produced when unit current passes through the cell Q5. wave motion has period T, frequency f, wavelength λ and speed ʋ. Which one of the following equations is incorrect? = Tf T = λ = Tʋ = λ Page 9 of 2

10 Q6. displacement The graph shows, at a particular instant, the variation of the displacement of the particles in a transverse progressive water wave, of wavelength 4 cm, travelling from left to right. Which one of the following statements is not true? The distance PS = 3 cm. The particle velocity at Q is a maximum. The particle at S is moving downwards Particles at P and R are in phase. Q7. Which one of the following types of wave cannot be polarised? radio ultraviolet microwave ultrasonic Page 0 of 2

11 Q8. The diagram shows two pulses on a string travelling towards each other. Which of the following diagrams shows the shape of the string when the pulses have passed through each other? Q9. Which one of the following statements about stationary waves is true? Particles between adjacent nodes all have the same amplitude. Particles between adjacent nodes are out of phase with each other. Particles immediately on either side of a node are moving in opposite directions. There is a minimum disturbance of the medium at an antinode. Q20. Which of the following is not a unit of power? N m s - kg m 2 s -3 J s - kg m - s - Page of 2

12 Q2. n object falls freely from rest. fter falling a distance d its velocity is v. What is its velocity after it has fallen a distance 2d? 2 v 4 v 2 v 2 2 v Q22. n electric motor of input power 00 W raises a mass of 0 kg vertically at a steady speed of 0.5 m s. What is the efficiency of the system? 5% 2% 50% 00% Page 2 of 2

13 Q23. The velocity of a vehicle varies with time as shown by the following graph. Which graph below represents how the resultant force F on the car varies during the same time? Page 3 of 2

14 Q24. ballbearing X of mass 2m is projected vertically upwards with speed u. ballbearing Y of mass m is projected at 30 to the horizontal with speed 2u at the same time. ir resistance is negligible. Which of the following statements is correct? The horizontal component of Y's velocity is u. The maximum height reached by Y is half that reached by X X and Y reach the ground at the same time. X reaches the ground first. Page 4 of 2

15 M. (a) γ / (pair of) gamma (ray(s))/z o (particles) (followed by gamma rays) / photon(s) of electromagnetic radiation (b) (i) mass can be converted to energy and vice versa (ii) charge baryon number lepton number minus for each incorrect answer if more than 3 answers are given 3 [5] M2. (a) Minimum energy to remove an electron from a (metal) surface 2 Page 5 of 2

16 (b) onverts 2.28 (e V) to (J) / ondone minus sign here on energy or charge Use of hf = ȹ 0 e.g. f = 2.28 / h (will need to see subject) or 2.28 = 6.6(3) 0 34 f or f = 2.28 / 6.6(3) 0 34 (will need to see subject ) Makes f subject or substitutes correctly for h and ȹ 0 allow equivalent substitution into hf = ȹ 0 + KE max where KE = 0 Penalise minus sign on answer (f =) 5.5(0) 0 4 (Hz) cao 3 [5] M3. (a) (i) π / 2 (radians) or 90 (degrees) No path differences Penalise contradictions No fractions of a cycle (ii) 3π / 2 (rad) or 270 (degrees) No path differences Penalise contradictions No fractions of a cycle (b) (oscillation or motion) perpendicular to direction of wave (travel / velocity / energy transfer) (oscillates from equilibrium to maximum positive displacement, back to equilibrium, then to max negative displacement) and back to equilibrium / starting position / rest position do not allow up and down for first mark allow up and down, or down then up, side to side, rise and fall in place of oscillates llow rest position, starting position, middle, centre line ref to nodes / antinodes not allowed for 2 nd mark 2 Page 6 of 2

17 (c) (the wave is) transverse OR not longitudinal accept it is an S wave or secondary wave only transverse can be polarised OR longitudinal waves cannot be polarised OR oscillations are in one plane 2 (d) (i) number of waves / complete cycles / wavelengths (passing a point / produced) per second or unit time allow: (number of) oscillations / vibrations / cycles per second allow f= / T only if T is correctly defined do not allow references to f=c / λ (ii) ( v = f / λ λ = v / f = ) / 6.0 = 750 (m) correct answer only gets 2 marks 2 [9] M4. (a) (i) use of OR t 2 = 2s / g t = = 0.49 ( s) allow 0.5 do not allow 0.50 Some working required for full marks. orrect answer only gets 2 3 (ii) (s = vt ) = ecf ai = 4.2 m (4.20) ecf from ai 2 (b) (i) t = or correct sub into equation above = = (s) (0.0824) allow 0.08 but not or 0. llow alternative correct approaches 2 Page 7 of 2

18 (ii) a = (v u) / t OR correct substitution OR a = 03 ( = 8.5 ) / = 03.2 ) (F = ma = ) 75 (03.2) ecf from bi for incorrect acceleration due to arithmetic error only, not a physics error (e.g. do not allow a = 8.5. Use of g gets zero for the question. = 7700 N (774) ecf (see above) Or from loss of KE Some working required for full marks. orrect answer only gets 2 3 [0] M5. (a) I 3 = I + I 2 (b) 0 V (c) I 2 = (2 0) / 0 = 0.2 llow ce for 0 V The first mark is for the pd The second is for the final answer (d) pd across R 2 increases s R increases, pd across R increases as pd = I R First mark is for identifying that pd across R increases (from zero). pd across R 3 = 0 V pd across R Therefore pd across R 3 decreases Second mark is for identifying that pd across R 3 must decrease pd across R 2 = 2 pd across R 3 Therefore pd across R 2 increases Third mark is for identifying that this means pd across R2 must increase [7] Page 8 of 2

19 M6. correct substitution of data in resistivity formula.() 0 6 () Ωm () [3] M7. M8. M9. M0. M. M2. M3. M4. M5. M6. Page 9 of 2

20 M7. M8. M9. M20. M2. M22. M23. M24. Page 20 of 2

21 Page 2 of 2