1 Which of the following is a vector quantity? flag bookmark A Pressure B Force C Momentum D Energy T4 Chapter 1.1 Physical Quantities A vector quantity has both magnitude and direction. Force and momentum are vectors (B and C), while pressure and energy are scalars. The answer scheme accepts both B and C.
2 Ahmad runs from rest and reaches his maximum velocity after accelerating uniformly for 10 seconds. If Ahmad's running displacement is 60 m, calculate his acceleration. flag bookmark A 1.20 m s⁻² B 1.25 m s⁻² C 2.10 m s⁻² D 2.50 m s⁻² T4 Chapter 2.1 Linear Motion Starting from rest, s = ½at², so 60 = ½ × a × 10², giving a = 1.20 m s⁻².
3 Amran throws a ball vertically upwards with an initial velocity of 15 m s⁻¹. Calculate the time for the ball to reach its maximum height. flag bookmark A 1.23 s B 1.25 s C 1.53 s D 1.55 s T4 Chapter 2.3 Free Fall Motion At the maximum height v = 0. Using v = u − gt, 0 = 15 − 9.81t, so t = 1.53 s.
4 Which of the following vehicles is the most difficult to stop when moving? flag bookmark A B C D T4 Chapter 2.4 Inertia Inertia depends on mass: the larger the mass, the harder it is to stop. The aeroplane (120 000 kg) has the largest mass.
5 Diagram 1 shows several firefighters holding a fire hose to put out a fire. Why does the fire hose have to be held by several firefighters? I To support the weight of the hose carrying the water. II To overcome the effect of a large backward jerk. III To increase the momentum of the water coming out. IV To add an impulsive force on the water that comes out. flag bookmark A I only B I and II C III and IV D I, II, III and IV T4 Chapter 2.5 Momentum The hose full of water is heavy (I), and the water shooting out forward with a large momentum gives the hose an equal backward momentum, a strong backward jerk (II), so several firefighters are needed.
6 Diagram 2 shows 4 points 0R, 1R, 2R and 3R from the centre of the Earth. Which point has the maximum value of gravitational acceleration? flag bookmark A 0R B 1R C 2R D 3R T4 Chapter 3.1 Newton's Universal Law of Gravitation From the graph, g increases from the centre up to the surface (1R) and then decreases with distance outside the Earth, so g is maximum at 1R, the Earth's surface.
7 The gravitational attraction between two bodies increases when their flag bookmark A masses are reduced and distance is reduced. B masses are increased and distance is reduced. C masses are reduced and distance is increased. D masses are increased and distance is increased. T4 Chapter 3.1 Newton's Universal Law of Gravitation By Newton's law of gravitation F = Gm₁m₂/r², the force increases when the masses increase and the distance decreases.
8 Diagram 3 shows a research satellite orbiting at an altitude of 400 km to capture images of an island in the middle of the ocean. What is the period of the satellite's orbit? [Radius of the orbit of the Moon, $r_B = 3.83 \times 10^{8}$ m, radius of the Earth, $R = 6.37 \times 10^{6}$ m, orbital period of the Moon = 655.2 hours] flag bookmark A 1.53 hours B 1.54 hours C 2.35 hours D 2.36 hours T4 Chapter 3.2 Kepler's Laws By Kepler's Third Law, T² ∝ r³. Satellite radius = 6.37 × 10⁶ + 4.0 × 10⁵ = 6.77 × 10⁶ m. T = 655.2 × (6.77 × 10⁶ ÷ 3.83 × 10⁸)^(3/2) = 655.2 × 0.00235 = 1.54 hours.
9 The Earth can maintain its layer of atmosphere because flag bookmark A the average linear speed of atmospheric gas molecules is less than the Earth's escape velocity B the average linear speed of atmospheric gas molecules is more than the Earth's escape velocity C the Earth's magnetic field D the gravitational effect of the Moon T4 Chapter 3.3 Man-made Satellites Gas molecules can escape only if their speed exceeds the escape velocity. The average speed of atmospheric molecules is much less than the Earth's escape velocity (about 11 km s⁻¹), so the atmosphere is kept.
10 Diagram 4 shows a metal spoon immersed in a cup of hot tea. Thermal equilibrium is reached when flag bookmark A the temperature of the metal spoon is higher than the temperature of the tea B the temperature of the tea is higher than the temperature of the metal spoon C the net rate of heat flow between the metal spoon and the tea is not zero D the net rate of heat flow between the metal spoon and the tea is zero T4 Chapter 4.1 Thermal Equilibrium Thermal equilibrium is reached when the spoon and the tea are at the same temperature, so the net rate of heat flow between them is zero.