RI Year 3 Physics MYCT 2017

NAME: CLASS: NO: RAFFLES INSTITUTION 2017 MID-YEAR COMMON TEST Subject Level Date Time PHYSICS YEAR 3 5 May 2017 (Friday) 0800– 0930 (1 h 30 min) INSTRUCTIONS 1. Do not turn over the page until you are told to do so. 2. Write your name, class and index number in the spaces at the top of this page. 3. Read all instructions and questions carefuly. 4. This paper consists of two sections. • Section A Answer all questions. Shade your answers in pencil on the separate OMR Sheet. Section B Answer all questions. Write your answers in the spaces provided. Use a blue or black pen. Question marked with an * is optional. Marks earned for this question will be credited as bonus marks. 5. All workings must be shown. 6. The marks shown indicate the relative credit intended for each part of a question. I. Candidates are reminded that all quantitative answers should include appropriate units and should be given to a sensible number of signi fi cant fi gures. Errors in units and numbers of signi fi cant fi gures will be penalized. SECTION A CONSISTS OF 8 PRINTED PAGES, EXCLUDING THE COVER PAGE. 265

1 rec aguired, you may assume that the gravitational acceleration or fi eld strength g ioWhere he 9.81 N kg. earth's surface is 9.81 m s² or Section A 18 marks] FOur possible ppropriate answe answers A, B, C and D are aiven for each question. Choose the mo nost mriate answer and shade your answers in pencil on the OMR answer sheet provided. .ornier caliper is being used to measure the thickness of a book. 5 6 cm 5 10 What is the reading of the vernier caliper? A 0.495 cm B 0.515 cm C 4.95 cm D 5.15 cm Certain phrases are used to describe errors in experimental measurements. X: Cannot be eliminated Y: Have a constant sign and magnitude Z: Cannot be reduced by averaging repeated measurements Which phrase/s describe random errors? A B C D only only X and Z Yand Z 267

2 3 Ihe following show markings made by arrows aimed at the bull's eye. Which shows results of high precision but low accuracy? (O ((O) A B C D 4 The fi gure below shows the speed-time graph for a car. v/m s1 10.0 8.0 4.0 3.0 5.0 tls What is the average speed of the car? A B C D 2.00 m s1 6.60 m s 7.33 m s1 8.00 m s1 268

3 nraph below shows the displacement-time graph of an object. The 5 sIm 4 X Y tls Which of the following section(s) shows the object accelerating? A B C D only X and Y only Y and Z only X, Y and Z A block of wood slides along a smooth horizontal surface with an initial velocity of 1.50 m s1 to the right. A gust of wind blowing horizontally towards the left slows the block down and reverses its direction of motion. After 10.0 s, the block achieves a fi nal velocity of 4.00 m s to the left. (Assume that the block experiences uniform acceleration throughout the motion.) 6 What is the change in displacement of the block in that period of 10.0 s? A B C D - 27.5 m 12.5 m 0.550 m 27.5 m 269

4 An Olympic diver jumps upwards from a tall diving platform. His trajectory is tracec diagram below. 7 Which of the following graphs below does not describe the motion of the diver from t he jumps off the platform to just before he hits the water? (Ignore effects of air resistance A B speed displacement 0 time time C D velocity acceleration 0 time 0 time 270

5 of the following vector diagrams represents three forces in equilibrium? Which oft 8 ? A B C D Two forces of magnitude 20.0 N and 10.0 N are exerted on a block resting on a smootn Surface, as shown in the fi gure below. 9 75° 20.0 N 10.0 N What is the horizontal component of the resultant force on the block? A (20.0- 10.0) N B C D (20.0- 10.0 cos 75°) N (20.0- 10.0 sin 75°) N (20.0- 10.0 tan 75°) N U A ball of mass m is thrown straight up into the air. Air resistance cannot be ignored. Vhat is the nmagnitude of the net force acting on the ball at the highest point of its path? A B C D zero between zero and mg equal to mg greater than mg 271

6 A car traveling at 30.0ms' strikes a low overhanging fruit from a tree. Which of the following statements about the forces of impact is true? A B C D 11 The net force on the fruit is zero. The force on the fruit is greater than the force on the car. The force on the fruit is equal to the force on the car. The force on the fruit is smaller than the force on the car. 12 In the absence of a net force, a moving object A B C will stop immediately will move with constant velocity may slow down and eventually stop may move with constant speed in a curved path D A circular turntable of radius 0.600 m is used for serving food and is free to rotate about its centre. A diner exerts a force of 5.00 N on the turntable as shown. 13 5.00 N 30° 0.600 m What is the magnitude of the moment due to the force about the centre? A B C O Nm 1.50 Nm 2.60 Nm 3.00 NmD 272

7 liagram shows a 0.400 kg sphere suspended by a light string from one end The diagram sh 14 rod. s The markings On the rod divide it into three equal sections. The rod is balanced at pivot as shown. 0.400 kg pivot What is the mass of the rod? 0.200 kg B 0.400 kg C 0.600 kg A D 0.800 kg 45 In the diagram, each object is made of materials of uniform density. steel object X plastic object Y Which of the following statements correctly describes the relative positions of the centre of gravity of each object? A The centre of gravity of X is lower than that of Y, because the density of X is larger than that of Y. B The centre of gravity of Y is lower than that of X, because the density of Y is lower than that of X. G The centre of gravity of Y is lower than that of X, because the base of Y is larger than its top. D Both the centres of gravity of X and Y are at the same height, because they are of the same height. 273

8 16 300 km h A plane, driven by a forward thrust of 2.00 x 10° N, fl ew at a constant velocitv of o. for 40.0 km. What is the magnitude of the work done by air resistance? A B C D 0J 1.67 x 10 J 6.00 x 10 J 8.00 x 10° J 17 A car speeds up as it ascends a slope. Which of the following describes the changes to its kinetic energy and its gravitatin nal potential energy? kinetic energy increases increases decreases decreases gravitational potential energy increases decreases increases decreases B 18 A battery can deliver 3000 J of energy to a small 2.0 W electric motor before the battery is exhausted. How many minutes does the motor run? A B C D 25 minutes 50 minutes 1500 minutes 6000 minutes 274

CLASS: NO: NAME: RAFFLES INSTITUTION UAM 2017 MID-YEAR COMMON TEST Subject Level Date PHYSICS (SECTION B) YEAR 3 5 May 2017 (Friday) FOR EXAMINERS USE Section Marks A 18 Q19 Q20 Q21 Q22 Q23 Q24 Q21(c) 10 B 9 6 Bonus Question 3 Penalty To t a l 60 SECTION B CONSISTS OF 11 PRINTED PAGES EXCLUDING THE COVER PAGE. 275