2021 SJI Physics Prelim P2

ST JOSEPH’S INSTITUTION PRELIMINARY EXAMINATION 2021 (YEAR 4) CANDIDATE NAME CLASS INDEX NUMBER PHYSICS Paper 2 6091/02 23 August 2021 1 hour 45 minutes (11:15 – 13:00) READ THESE INSTRUCTIONS FIRST Write your name, class and index number on the cover page of this Question Paper and all the work you hand in. Write in dark blue or black pen on both sides of the paper. You may use a soft pencil for any diagrams or graphs. Do not use paper clips, highlighters, glue or correction fluid. Section A Answer all questions on the Question paper. Section B Answer all questions. Question 12 has a choice of parts to answer. Candidates are reminded that all quantitative answers should include appropriate units. Candidates are advised to show formulae and 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. Section A Q1 Q2 Q3 Q4 Q5 Q6 Q7 Q8 Q9 For Examiner’s Use Section A / 50 Section B / 30 Total / 80 This document consists of 24 printed pages including this cover page

2 Section A (50 marks) Answer all questions in this section. 1 A ball is thrown vertically upwards. (a) If the ball is thrown with a velocity of 9.2 m/s, calculate the velocity of the ball 0.42 s after it has been thrown. Take acceleration due to gravity to be 10 m/s2. velocity = ……………………….. [2] (b) Calculate the maximum height the ball will reach. maximum height = ……………………….. [2] (c) In Fig. 1.1, sketch how the ball’s displacement changes with time, from the moment it is thrown, until the time it returns to the thrower. Take its initial displacement to be 0.0 m. [1] Fig. 1.1 (d) Explain why the ball reaches a lower maximum height when there is air resistance. …………………………………………………………………………………………. ……………………………………………………………………………………… [1]

3 2 Fig. 2.1 shows a 5.0 kg object being pulled by a string at an angle of 60° to the horizontal. The string exerts a constant tension on the object, causing it to slide on the smooth horizontal surface at a constant acceleration of 0.50 m/s2. Air resistance can be ignored. Fig. 2.1 (a) Calculate the resultant force acting on the object. resultant force = ……………………….. [1] (b) In the space below, draw a labelled diagram to show the resultant of all the forces acting on the object. Determine the magnitude of the tension of the string. tension = ……………………….. [3]

4 (c) A student suggests that since the object is moving horizontally, the vertical component of the tension of the string must be equa