ADSS Prelim P2

This question paper consists of 26 printed pages including this cover page. ADMIRALTY SECONDARY SCHOOL SUBJECT : Physics CODE/PAPER : 6091/2 LEVEL/STREAM : Secondary 4 Express DATE : 22 Aug 2024 TIME : 0800h – 0945h DURATION : 1 hour 45 minutes READ THESE INSTRUCTIONS FIRST Write your name, class and register number on all the work you hand in. Write in dark blue or black pen. You may use an HB pencil for any diagrams, graphs, tables or rough working. 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, where 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. DO NOT TURN OVER THIS PAPER UNTIL YOU ARE TOLD TO DO SO. PRELIMINARY EXAMINATION 2024 For Examiner’s Use Section A / 70 Section B / 10 Total / 80 NAME: NO: CLASS:

2 Section A Answer all questions. 1 Fig. 1.1 shows the speed-time graph for a rocket from the moment the fuel starts to burn at t = 0 s. Fig. 1.1 (a) Describe the motion of the rocket between t = 5 s and t = 100 s. ……………………………………………………………………………………………… ……………………………………………………………………………………………… ……………………………………………………………………………………………… ……………………………………………………………………………………………… [3] (b) The total mass of the rocket at t = 80 s is 1.6 x 106 kg. Calculate the upward force on the rocket due to the burning fuel at this time. upward force = ………………………………..… [2] 1400 1200 1000 800 600 400 200 0 0 20 40 60 80 100 t / s speed m/s

3 2 A swing is made by connecting a car tyre to the wire using a rope and a hook. The wire hangs between two fixed points, as shown in Fig. 2.1. Fig. 2.1 The tyre is hanging in equilibrium with the wire hanging at an angle of 17 to the horizontal. The tension in the wire is 150 N. Assume that the rope and hook have negligible weight. (a) In the space provided, draw a labelled diagram to show the resultant of the two tensions. Determine the size of the resultant force and the direction between the resultant force and the horizontal. scale = ……………………………….. resultant force = ….………………..…… direction = ………………………………... [4] fixed point fixed point hook wire 150 N 150 N 17o 17o tyre rope

4 (b) State and explain the weight of the tyre. …………………………………………………………………………………………… …………………………………………………………………………………………… …………………………………………………………………………………………… [2] 3 Fig. 3.1 shows a trash bin with a lid opener mechanism. When the foot pedal is pressed, it pulls the rope downwards and exerts a tension force on the handle. This force creates a turning effect about the point X, allowing the lid to open. Fig. 3.1 (a) State what is meant by the “Principle of Moments”. …………………………………………………………………………………………...… …………………………………………………………………………………………...… …………………………………………………………………………………………...… [1] handle W X 20 N rope pedal 10 cm

5 (b) The perpendicular distance from the pivot X to the tension T in the rope is 1.2 cm. Calculate the moment about X due to the tension in the rope. moment = ……………………. [2] (c) The weight of the lid is W. Hence, or otherwise, calculate the mass of the lid. mass = ……………………. [2] (d) Suggest a modification to the design of this trash bin to improve its stability. …………………………………………………………………………………………...… …………………………………………………………………………………………...… [1]

6 4 Fig. 4.1 shows a manometer joined to a cylinder containing a gas. The piston has a cross-sectional area of 0.050 m2. Fig. 4.1 A metre rule is placed beside the manometer. The pressure exerted by the gas is 104 kPa. Take atmospheric pressure to be 100 kPa. The gravitational field strength g is 10 N/kg. (a) Determine the density of the liquid in the manometer. density = …………………………. [2] (b) The cylinder is heated and the piston is allowed to move a distance of 8.0 cm. The pressure of the gas in the cylinder remains constant. (i) Calculate the work done by the gas to move the piston. work done = …………………………. [2] metre rule piston cylinder gas manometer cm

7 (ii) Explain, using the kinetic model of matter, why the pressure of the gas remains constant even though the cylinder is heated. ……………………………………………………………………………………….. ……………………………………………………………………………………….. ……………………………………………………………………………………….. ……………………………………………………………………………………….. [3]

8 5 Fig. 5.1 shows a log sliding down an earth slope from X to Y to Z. Fig. 5.1 (a) The log has a mass of 500 kg and its speed at point Y is 5.5 m/s. The gravitational field strength g is 10 N/kg. (i) Calculate the energy in the kinetic store of the log at point Y. energy in the kinetic store = ………………………………….[1] (ii) Calculate the amount of work done against friction between X and Y. work done = ………………………………….[2] 6 m Y  Z  20 m  X log

9 (b) The log stops at point Z. Explain, using energy transfer, why the log stops. …………………………………………………………………………………………...… …………………………………………………………………………………………...… …………………………………………………………………………………………...… [2]

10 6 In a particular experiment, a student suspended a 600 W immersion heater in a beaker of boiling water. He ensured that the heater was completely submerged in the water but did not touch the bottom of the beaker as shown in Fig. 6.1. Fig. 6.1 He then placed the beaker with the immersion heater on an electronic mass balance and obtained the following readings: reading on the mass balance when water started to boil = 569.931 g reading on the mass balance after water boiled for one minute = 569.016 g (a) (i) Calculate a value for the specific latent heat of vaporization of water, lV. lV = …………………….[2] (ii) State and explain whether you would expect the answer in part (a)(i) to be an overestimation or an underestimation of the actual value of lV. ……………………………………………………………………………………….. ……………………………………………………………………………………….. ……………………………………………………………………………………….. [2] 569.931 g electronic mass balance immersion heater to power supply