BBSS 4E O Prelim 2024 Physics 6091 P2 QP

Bukit Batok Secondary School GCE O LEVEL PRELIMINARY EXAMINATION 2024 SECONDARY 4 EXPRESS PHYSICS 6091/02 Paper 2 Structured and Free Response 23 Aug 2024 1 hour 45 minutes 1050 – 1235 h Candidates answer on the Question Paper. No Additional Materials are required. READ THESE INSTRUCTIONS FIRST Write your Centre number, index number and class on all the work you hand in. Write in dark blue or black pen. You may use an HB pencil for any diagrams or graphs. Do not use staples, paper clips, glue or correction fluid. Section A Answer all questions. Write your answers in the spaces provided. Section B Answer one question. Write your answers in the spaces provided. Candidates are reminded that all quantitative answers should include appropriate units. The use of an approved scientific calculator is expected, were appropriate. Candidates are advised to show all their working in a clear and orderly manner, as more marks are awarded for sound use of Physics than for correct answers. The number of marks is given in brackets [ ] at the end of each question or part question. This Question paper consists of 23 printed pages including this cover page For Examiner’s Use Section A Section B Total Name: …………………………………………. Index no. ………. Class……….

BBSS/Preliminary Exam 2024/Physics 6091/Paper 2 Applying past knowledge to new situations 2 Section A Answer all the questions. 1 In a fireworks display, a 4.0 kg rocket is launched vertically upwards from the ground into the air. The rocket runs out of fuel when moving with a velocity of 64 m/s. Fig. 1.1 shows how the velocity of the rocket varies with time until it reaches ground. Assume that air resistance can be neglected. Fig. 1.1 (a) Describe the direction of motion and acceleration of the rocket from time t = 0 s to t = 50 s. ……………………………………………………………………………………… ……………………………………………………………………………………… ……………………………………………………………………………………… ……………………………………………………………………………………… [2] (b) State the time at which the rocket reaches its highest point. time = ………………… [1] 10 50 40 30 20 90 80 70 60100 0 20 - 2 0 60 40 - 80 - 40 - 60 v = 64 18 velocity / m/s time / s

BBSS/Preliminary Exam 2024/Physics 6091/Paper 2 Applying past knowledge to new situations 3 (c) Using Fig. 1.1, calculate the maximum height reached by the rocket maximum height = ………………… [2] 2 Fig. 2.1 shows the vertical forces acting on a skydiver a few seconds after he jumps off the plane. Fig. 2.1 The skydiver experiences an upward force of 20 N. The weight of the skydiver is 700 N. (a) Define gravitational field strength. ……………………………………………………………………………………… ……………………………………………………………………………………… [1] (b) Determine the mass of the skydiver. The gravitational field strength g is 10 N/kg. mass = ………………… [1]

BBSS/Preliminary Exam 2024/Physics 6091/Paper 2 Applying past knowledge to new situations 4 (c) Calculate the vertical acceleration of the skydiver in Fig 2.1. acceleration = ………………… [2] (d) Use Newton’s laws of motion to explain why the skydiver accelerates at first and then reaches terminal velocity. ……………………………………………………………………………………… ……………………………………………………………………………………… ……………………………………………………………………………………… ……………………………………………………………………………………… ……………………………………………………………………………………… [2] (e) The weight of the skydiver is one of the two forces that form an action- reaction pair of forces. State and describe the other force of this pair when the air resistance reaches 700 N. ……………………………………………………………………………………… ……………………………………………………………………………………… [2]

BBSS/Preliminary Exam 2024/Physics 6091/Paper 2 Applying past knowledge to new situations 5 3 Fig 3.1 shows an air cushion connected to a mercury manometer. Before the 50 kg mass is placed on the air cushion, the air pressure inside the air cushion is the same as the atmospheric pressure. When a 50 kg mass is placed on the air cushion, the manometer shows the heights difference between the two columns. The atmospheric pressure is 76 cmHg. Fig. 3.1 (a) Calculate the pressure (in cmHg) of the air cushion. pressure = ……........................cmHg [2] (b) The density of mercury is 13 600 kg/m3. Calculate the contact area between the 50 kg mass and the air cushion. The gravitational field strength g is 10 N/kg. area = ………………… [3]

BBSS/Preliminary Exam 2024/Physics 6091/Paper 2 Applying past knowledge to new situations 6 4 Fig. 4.1 shows a 0.50 kg ball sliding down a rough incline from position A which is 7.5 m above the ground with an initial speed of v o m/s. Friction along the incline produces 10.7 J of thermal energy . The initial speed v o decreases as the ball rolls down the incline to position B . The ball leaves the incline at position B moving vertically upward and reaches a height of 13.0 m above the floor at position C. Fig. 4.1 (a) Using the concept of energy stores and transfers, explain the changes in the energy within the ball and its effects on the ball as it rolls down from position A to B. ……………………………………………………………………………………… ……………………………………………………………………………………… ……………………………………………………………………………………… ……………………………………………………………………………………… ……………………………………………………………………………………… ……………………………………………………………………………………… ……………………………………………………………………………………… ……………………………………………………………………………………… [4] (b) (i) Calculate the gravitational potential store of the ball at position C. gravitational potential store = ………………… [1]

BBSS/Preliminary Exam 2024/Physics 6091/Paper 2 Applying past knowledge to new situations 7 (ii) Calculate the initial speed v0, at position A. v0 = ………………… [2] (c) State one assumption for your calculations in (b)(ii). ……………………………………………………………………………………… ……………………………………………………………………………………… [1]

BBSS/Preliminary Exam 2024/Physics 6091/Paper 2 Applying past knowledge to new situations 8 5 In a bicycle shop, two wheels hang in equilibrium from a horizontal uniform rod AC, as shown in Fig. 5.1. Fig. 5.1 The rod has weight 19 N and is freely hinged to a wall at end A. The other end C of the rod is attached by a vertical elastic cord to the ceiling. The centre of gravity of the rod is at point B. The weight of each wheel is W and the tension in the cord is 22 N. (a) State the principle of moments. ……………………………………………………………………………………… ……………………………………………………………………………………… [2] (b) By taking moments about end A, show that the weight W of each wheel is 14 N. [2] (c) Determine the magnitude and the direction of the force acting on the rod at end A. magnitude = ………………… direction = ………………… [1]

BBSS/Preliminary Exam 2024/Physics 6091/Paper 2 Applying past knowledge to new situations 9 6 A student compares two electric heaters that are used at home. Fig. 6.1 shows the design of electric heater X while Fig.6.2 shows the design of electric heater Y. Each heater consists of an identical tank to contain the same volume of water and an identical electrical heating element at the bottom of t