霹雳怡保培南独立中学 SM POI LAM (SUWA) IPOH MID-YEAR EXAMINATION 2022 PHYSICS Paper 2 DATE: 12 th May 2022 (Thursday) TIME: 1335 – 1535 (120 minutes) NAME: _________________________ REG. NO: ___________ CLASS: S3 LI READ THESE INSTRUCTIONS FIRST 1. This subject comprises two papers: Paper 1: Multiple-choice questions (30%) Paper 2: Subjective questions (70%) 2. There are two sections which are Section A and Section B in paper 2. You are required to answer All questions in Section A and choose Only Four questions from Section B. 3. Electronic calculators may be used. 4. The data of constant is on page 2. The total mark for this paper is 70. Do Not Turn Over This Page Until You Are Told To Do So This paper consists of 7 printed pages (including this page) Prepared by: Checked by: _________________ __________________ (ONG KAR WENG) (LING SOON CHING)
2 Data of Constant: * Speed of light c = 3.0 x 108 ms-1 * Acceleration due to gravity g = 9.8 ms-2 * Gravitational Constant G = 6.67 x 10-11 Nm2 kg-2 * Specific heat capacity of water c = 4200 Jkg-1K-1 * Electron Charge e = -1.6 x 10-19 C * Electron mass me = 9.1 x 10-31 kg * Permittivity of free space εo = 8.854 x 10-12 F m-1 * Planck Constant h = 6.6 x 10-34 Js * Avogadro’s Number NA = 6.02 x 1023 mol-1 * Molar gas constant R = 8.314 Jmol-1K-1 * Boltzmann constant k = 1.38 x 10-23 m2kgs-2K-1 * Permeability of free space µo = 4π x 10-7 TmA-1
3 Subjective Questions (70%) Section A (30%) Answer all five questions. 1. A ball of mass 800 g is dropped from a height of 5.0 m and rebounds to a height of 3.8 m. The air resistance is negligible. Calculate: (a) the kinetic energy of the ball just before impact (2%) (b) the intial rebound speed of ball (2%) (c) the energy transferred to the ground during the impact. (2%) 2. A 50 g mass is attached to a securely clamped spring. The mass is pulled downwards by 16 mm and released, which causes it to oscillate with S.H.M of time period of 0.84 s. (a) Calculate the frequency of the oscillation. (2%) (b) Calculate the maximum velocity of the mass. (2%) (c) Calculate the maximum kinetic energy of the mass and state at which point in the oscillation it will have this velocity. (2%) 3. A car of mass 1100 kg is travelling at 24 m s−1 . The driver applies the brakes and the car decelerates uniformly and comes to rest in 20 s. (a) Calculate the change in momentum of the car. (2%) (b) Calculate the braking force on the car. (2%) (c) Determine the braking distance of the car. (2%) 4. Find the energy of the following gas molecules at 300K. (a) An oxygen molecule (2%) (b) A helium molecule (2%) (c) A carbon dioxide molecule. (2%) 5. A metal sheet has dimensions of 2 m x 1m x 5 cm is heated up from 20oC to 800oC, what is the expansion value of (a) Length (2%) (b) Area (2%) (c) Volume (2%) (Coefficient of linear expansion, α = 1.2 x 10-5 )
4 Section B (40%) Answer Only Four questions from this section. 1. (a) Figure 1 shows a P-V graph. Given that line CD is constant pressure line. Line AD and BC is constant temperature line. Temperature at line AD is 250 K. Find the (i) pressure of state B. (2%) (ii) temperature of state B. (2%) Figure 1 (b) A closed cylinder of volume 5 x 10-3 m3 contains 1.6 moles of hydrogen. The pressure of gas in the cylinder is 1.4 x 106 Pa. Calculate (i) Temperature of the gas (2%) (ii) The internal energy of the gas (2%) (iii) The r.m.s speed of hydrogen molecules. (2%) [Mass of 1 mole of hydrogen = 0.002 kg ] 2. (a) A refrigerator has dimensions of 30cm x 20cm x 50cm , with its wall thickness 1.5 cm contains 20 kg of ice ( 0oC) . If the thermal conductivity , k of the wall is 2.3 x 10-2 Wm-1 oC -1 , while the temperature outside the refrigerator is 25oC, how long is the time taken to melt the ice completely? (Given latent heat of fusion for ice , Lf = 3.36 x 105 J kg-1 ) (4%)
5 (b) A matter with mass of 2 kg, is freezing after the process of melting as shown in figure 2. The heat energy provided by heater is 800 J per minute. Figure2 (i) The freezing point of matter is______0C。 (1%) (ii) The latent heat of fusion of matter is ______________。 (2%) (iii) The specific heat capacity of matter during solid state is _______。 (2%) (iv) What is the temperature of the matter during 70th minutes? (1%) 3. (a) The figure 3 shows a system which is in equilibrium. The block of mass 5kg on the table is about to slide. Figure 3 (i) Draw a vector diagram for the equilibrium of point O. (1%) (ii) Find the magnitude of the forces along the string OP and OQ. (2%) (iii) Calculate coefficient of static friction between the 5kg mass and the table. (2%) Temperature (0C) Time (minutes)
6 (b) Figure 4 shows a worker uses a pulley to raise a load of 60 kg from rest. He applies a constant force of 1000N. The friction in the pulley is 250N. Figure 4 Calculate (i) The acceleration of the load (2%) (ii) The kinetic energy of the load after 2.0 s (2%) (iii) The work done by the worker. (1%) 4. Two balls P and Q of mass 1 kg and 5 kg respectively collide head-on on a smooth horizontal surface and their displacement-time graphs before and after the collision are as shown in figure 5. Figure 5 (a)When does the collision between the balls occur? (1%) (b) (i) Describe the states of motion of the two balls before and after collision. (2%) (ii) Find the velocities of the ball P and Q before and after collision. (2%) (c)Calculate and determine if the total momentum and the total kinetic energy are conserved before and after the collision. (5%)
7 5. As shown in figure 6 below, a bullet A of mass 100g travels horizontally with initial velocity u towards a wooden ball B of mass 500g, which is suspended from point O by a light string of length L = 0.5m. After collision, the bullet A remains embedded in ball B and move upwards in a vertical circle. If the objects can just reach the highest point C and complete the circular motion, Figure 6 Determine (a) The speed of the bodies at C; (2%) (b) The speed of the bodies immediately after the collision. (3%) (c) The initial velocity u of the bullet; (3%) (d) The energy lost by the system due to the collision. (2%) 6. A ball is thrown against a vertical wall. The path of the ball is shown in figure 7. Figure 7 The ball is thrown from S with an initial velocity of 15ms-1 at 60°to the horizontal. Assume that air resistance is negligible. (a) For the ball at S, calculate (i) its horizontal component of velocity (1%) (ii) its vertical component of velocity (1%) (b) The horizontal distance from S to the wall is 9.95 m. The ball hits the wall at P with a velocity that is at right angles to the wall. The ball rebounds to a point F that is 6.15m from the wall. (i) find the vertical height gained by the ball when it travels from S to P. (2%) (ii) show that the time taken for the ball to travel from S to P is 1.33s. (2%) (iii) show that the velocity of the ball after rebounding from the wall is about 4.6ms-1 . (2%) (c) The mass of the ball is 60g. Calculate the change in momentum of the ball as it rebounds from the wall. (2%) ----------------------------------------------------End of Exam Paper --------------------------------------------- Bullet