NYGH 2017-S3EOY-Physics P2

Class Register Number Name 南洋女子中学校 NANYANG GIRLS’ HIGH SCHOOL End-of-Year Examination 2017 Secondary Three PHYSICS 1 hour 45 minutes Paper 2 Theory Paper 10:30 – 12:15 Monday 9 October 2017 No additional materials are required. READ THESE INSTRUCTIONS FIRST Do not open this booklet until you are told to do so. Write your name, register number and class in the spaces at the top of this page and on any separate answer paper used. Write in dark blue or black ink. You may use a pencil for any diagrams or graphs. Do not use correction fluid or tape. Section A (40 marks) Answer all questions. Write your answers in the spaces provided on the question paper. Section B (30 marks) Answer all questions. Question 11 has a choice of parts to answer: 11 Either or 11 Or. Write your answers in the spaces provided on the question paper. At the end of the examination, circle 11 Either or 11 Or in the grid on the right to indicate which question you have answered. INFORMATION FOR CANDIDATES The intended number of marks is given in the brackets [ ] at the end of each question or part question. You are advised to spend no longer than one hour on Section A and no longer than 45 minutes on Section B. Candidates are reminded that all quantitative answers should include appropriate units. 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 use of an approved scientific calculator is expected, where appropriate. The acceleration due to gravity (or gravitational field strength) g is taken to be 10 m s-2 (or 10 N kg-1) near the Earth’s surface. Examiner’s Use Section A (40 marks) 1 2 3 4 5 6 7 8 Section B (30 marks) 9 10 11 Either 11 Or Paper 2 (70 marks) Paper 1 (30 marks) Overall % This document consists of 17 printed pages and 1 blank page. Setters: AJL & CMH NANYANG GIRLS’ HIGH

2017 End-of-Year Examination Secondary Three 2 Nanyang Girls’ High School Setters: AJL & CMH Physics II Section A (40 marks) Answer all questions. 1 A springbok is a type of antelope. When it is startled, it will leap s traight up into the air in a manner called a “pronk”. A springbok goes into a crouch (lowers its body) to perform a pronk. It then extends its legs forcefully, accelerating at 35 m s -2 for 0.70 m vertically as its legs straighten. When its legs are fully extended (as shown in Fig. 1.1), it leaves the ground and rises into the air. Fig. 1.1 (a) Determine the speed at which the springbok just leaves the ground. speed = ……………………………. [2] (b) The springbok can jump to a large vertical height after leaving the ground. Using the axes in Fig. 1.2, sketch a graph of speed against time for the springbok doing a “pronk”, from the crouch to the highest point of its jump. No calculation or labelling is needed. Neglect air resistance. [1] Fig. 1.2 speed / m s-1 time / s 0 Source: https://www.saatchiart.com/art/Drawing- Pronk/517846/2806964/view

2017 End-of-Year Examination Secondary Three 3 Nanyang Girls’ High School Setters: AJL & CMH Physics II [Turn over 2 A helicopter is sent out from a hospital to rescue someone in the sea. Its motion along the horizontal direction is shown by the velocity-time graph in Fig. 2.1. Fig. 2.1 (a) Describe clearly the horizontal motion of the helicopter from 0 to 2.5 hours shown in Fig. 2.1. ……………………………………………………………………………………………… ……………………………………………………………………………………………… ……………………………………………………………………………………………… ……………………………………………………………………………………………… …………………………………………………………………………………………... [3] (b) Determine the displacement of the helicopter from 0 to 1.5 hours. displacement = ……………………………. [2] time / hours 1 2 3 velocity / m s−1 100 50 −50 0 −100

2017 End-of-Year Examination Secondary Three 4 Nanyang Girls’ High School Setters: AJL & CMH Physics II 3 Fig. 3.1 shows three blocks connected by inextensible strings on a frictionless surface. The masses of the blocks are 24 kg, 14 kg and 12 kg respectively. A force of 20 N is pulling the system to the right such that the blocks move together. Fig. 3.1 (a) Calculate the acceleration of the blocks. acceleration = ……………………………. [2] (b) Determine the tension in string 1. tension = ……………………………. [2] (c) Compare the tension in strings 1 and 2. Explain your reasoning clearly. ……………………………………………………………………………………………… ……………………………………………………………………………………………… …………………………………………………………………………………………... [2]

2017 End-of-Year Examination Secondary Three 5 Nanyang Girls’ High School Setters: AJL & CMH Physics II [Turn over 4 In Sentosa, visitors can enjoy rides on luge carts (see Fig. 4.1) downslope along a trail. Fig. 4.1 (a) Fig. 4.2 shows a simplified diagram of the luge cart. Draw and label all the forces acting on the luge cart. Neglect air resistance. [2] Fig. 4.2 (b) Explain what “moves” a luge cart down a slope. ……………………………………………………………………………………………… …………………………………………………………………………………………... [1] (c) A luge cart moves down a slope at 20° to the horizontal as shown in Fig. 4.2. The cart is moving in a straight line with constant speed. Draw and label a vector diagram (not to scale) below to show the addition of all the forces identified in part (a). [2] Source: http://www.maritour.com/wp- content/uploads/2016/02/SINGAPORE- LUGE-SENTOSA.jpg luge cart slope 20°

2017 End-of-Year Examination Secondary Three 6 Nanyang Girls’ High School Setters: AJL & CMH Physics II (d) If the mass of the luge cart is 25 kg, calculate the frictional force acting on the cart. frictional force = ……………………………. [2] 5 A toy is constructed with two heavy spheres J and K, a plastic rod and some w ire as shown in Fig. 5.1. The toy is placed on a support where it remains balanced. Fig. 5.1 (a) Define centre of gravity. ……………………………………………………………………………………………… …………………………………………………………………………………………... [1] (b) The plastic rod and the wire have negligible weight. Mark on Fig. 5.1 the centre of gravity of the toy with a cross “x”. [1] (c) Explain why the toy does not topple when sphere K is pushed towards the left. ……………………………………………………………………………………………… ……………………………………………………………………………………………… …………………………………………………………………………………………... [2] wire plastic rod support K J

2017 End-of-Year Examination Secondary Three 7 Nanyang Girls’ High School Setters: AJL & CMH Physics II [Turn over 6 A car crusher is used to reduce the dimensions of cars before they are sent for recycling. The car crusher makes use of a hydraulic system to set up the large force required to crush a car. Fig. 6.1 shows a simple hydraulic system. Fig. 6.1 (a) State two properties of the hydraulic liquid that allow hydraulic systems to work. 1. .…………………………………………………………………………………………. ……………………………………………………………………………………… [1] 2. .…………………………………………………………………………………………. ……………………………………………………………………………………… [1] (b) A typical crushing plate has an area of 13.0 m 2. If the force required to crush a car is 155 kN, calculate the pressure that must be set up at the small piston. pressure = ……………………………. [2] small piston crushing plate car to be crushed hydraulic liquid

2017 End-of-Year Examination Secondary Three 8 Nanyang Girls’ High School Setters: AJL & CMH Physics II 7 The Taipei 101 in Taiwan is a 101- storey skyscraper. The skyscraper is the home of the world’s fastest elevator. The