*2. 1.The diagram below shows the forces acting on a block of weight W as it slides down a slope.The angle between the slope and the horizontal is θ, the normal reaction force on the block from the slope is N and friction is negligible.
Which of the following gives the resultant force on the block?
A. W sin θ
B. W cos θ
C. N sin θ
D. N cos θ
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*3. 2. The velocity–time graph for an accelerating object that is travelling in a straight line is shown below.Which of the following is the change in displacement of the object in the first 5.0 seconds?
A. 25.0 m
B. 12.5 m
C. 5.0 m
D. 1.0 m
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*4. 3. The momentum of an object changes by ∆p in a time ∆t. What is the impulse acting on the object during this change?
A.
B.
C.
D. zero
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*5. 4.A pendulum swings back and forth in a circular arc between X and Y.The pendulum bob is
A. always in equilibrium.
B. only in equilibrium at X and Y.
C. in equilibrium as it passes through the central position.
D. never in equilibrium.
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*6. 5. A car moves at constant speed around a horizontal circular track. The resultant force on the car is always equal to
A. the forward force from the engine.
B. the sideways friction between the tyres and the track.
C. the weight of the car.
D. zero.
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*7. 6. An ideal gas has an absolute temperature T. The average random kinetic energy of the molecules ofthe gas is
A. independent of T.
B. equal to T.
C. proportional to T.
D. inversely proportional to T.
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*8. 7. An object is undergoing simple harmonic motion (SHM) about a fixed point P. The magnitude of its placement from P is x. Which of the following is correct?
A.
B.
C.
D.
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*9. 8. Which of the following gives the conditions for maximum amplitude in forced, but damped, oscillations?
A.
B.
C.
D.
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*10. 9. A ray of light travels from a vacuum into glass as shown below.In glass, light has speed v . In a vacuum, light has speed c. Which of the following gives the refractive index of glass?
A.
B.
C.
D.
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*11. 10. A transverse standing wave is established on a string. Consider the following phase differences.
I. 0°
II. 90°
III. 180°
Which of the following gives all the possible phase differences between the oscillations of any two particles in the standing wave?
A. I only
B. I and III only
C. II and III only
D. I, II and III
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*12. 11. Which of the following would be diffracted the most when incident on a slit of width 1 cm?
A. microwaves
B. red light
C. ultraviolet
D. X-rays
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*13. 12. A battery of emf 6.0 V is connected to a 2.0 Ω resistor. The current in the circuit is 2.0A. The internal resistance of the battery is
A. zero.
B. 1.0 Ω.
C. 3.0 Ω.
D. 4.0 Ω.
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*14. 13. Which of the following gives the resistances of an ideal ammeter and an ideal voltmeter?
A.
B.
C.
D.
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*15. 14. A mass at point X gives rise to a gravitational field strength g at point P as shown below.An identical mass is placed at point Y as shown below.
The resultant gravitational field strength at P is now
A. greater than 2g.
B.between 2g and g.
C. between g and zero.
D. zero.
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*16. 15. A proton p is at rest between the poles of two horizontal magnets as shown below.The magnetic force on the proton is
A. from left to right.
B. from top to bottom.
C. into the plane of the paper.
D. zero.
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*17. 16. A gun fires a bullet of mass m at a horizontal velocity of v. Air resistance on the bullet is negligible.A change in which of the following will affect the time for the bullet to hit the ground?
A. m only
B. v only
C. m and v
D. neither m nor v
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*18. 17. At the surface of a planet of radius r, the gravitational potential is – 6.4 ´ 107 J kg–1. The gravitational potential at a height of r above the surface is
A.
B.
C.
D.
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*19. 18. An astronaut of mass 60 kg is on board the International Space Station, which is in low orbit around the Earth. The gravitational force of attraction between the Earth and astronaut is approximately
A. zero.
B. 6 N.
C. 60 N.
D. 600 N.
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*20. 19. A length of copper wire PQ is moved downwards through the poles of two horizontal bar magnets as shown below.Compared to end Q, end P will have
A. fewer electrons.
B. more electrons.
C. fewer protons.
D. more protons.
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*21. 20. The rms voltage of a sinusoidal electricity supply is 110 V. The maximum potential difference during one cycle is
A. 220 V.
B.156 V.
C. 110 V.
D. 55 V.
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*22. 21. All isotopes of uranium must have the same
A. chemical properties.
B. mass.
C. half-life.
D. decay constant.
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*23. 22. A unit in which mass defect can be measured is
A. MeV.
B. MeV c–1.
C. MeV c–2.
D. MeV per nucleon.
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*24. 23. When compared with beta particles and gamma-ray photons, alpha particles have the greatest
A. mass.
B. penetrating power.
C. range in air.
D. speed.
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*25. 24. Light of a particular wavelength and intensity does not cause photoelectric emission from a clean metal surface in a vacuum. Which of the following changes to the light might cause photoelectric emission?
A. Increase the intensity
B. Decrease the intensity
C. Increase the wavelength
D. Decrease the wavelength
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*26. 25. Alpha particles of charge +2e and mass m are accelerated from rest through a potential difference V.Planck’s constant is h. Which of the following gives the de Broglie wavelength of the alpha particles as a result of the acceleration?
A.
B.
C.
D. hmV
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*27. 26. The lowest four energy levels of a particular atom are represented in the energy level diagram below.Planck’s constant is h. What is the highest frequency in the atom’s emission spectrum that is associated with these levels?