Raffles Institution 2018 Y4 FE Sections A and B

1 35 30 25 0 5 5 0 45 40 0 Section A [30 marks] Four possible answers A, B, C and D are given for each question. Choose the most appropriate answer and shade your answers in pencil on the OTAS answer sheet provided. 1 Which quantity is a base quantity? A length B heat C weight D potential difference 2 The diagrams below show the readings of a micrometer screw gauge when it is closed fully and when it is measuring the diameter of a marble. fully closed measuring diameter of marble What is the diameter of this marble? A 7.33 mm B 7.73 mm C 7.83 mm D 8.23 mm 3 A student carries out an experiment to investigate how the length of a pendulum will affect the period of oscillation of the pendulum bob. Throughout the experiment, the student realises that there are some steps that may result in errors in his results. A brief description of these steps are as follows: Step P: The length of pendulum is measured from a blunt edge of a metre rule. Step Q: The time taken for the oscillation of pendulum bob i s recorded using a handheld stopwatch. Step R: He starts timing the period of oscillation immediately upon the release of the pendulum.

2 Step S: The size of the pendulum bob is measured using a micrometer screw gauge with an initial reading of 0.01 mm when fully closed without any measurement. Which of the following shows the correct classification of the errors identified? systematic error(s) random error(s) A Step R, Step S Step P, Step Q B Step P, Step S Step Q, Step R C Step S Step P, Step Q, Step R D Step P, Step R, Step S Step Q 4 At the 9 km mark, a runner records an initial velocity of 2.00 m / s. Assume that at the last kilometre (from 9 km mark to the 10 km mark), the runner accelerates at an uniform rate of 0.0100 m / s2. How long does the runner take to travel the last kilometre? A 290 s B 500 s C 690 s D 2710 s 5 An object is thrown vertically up wards with an initial velocity, vo, and it returns to the same initial position in the absence of air resistance. If the same experiment is carried out in the presence of air resistance, which statement is false? A The time taken for the object to reach zero velocity is smaller. B The total distance travelled by the object is shorter. C The velocity when the object lands back at the initial position is smaller than vo. D The net acceleration is the same throughout the motion.

3 6 A crate of mass 5.00 kg, is placed on a rough slope inclined at angle, θ. It experiences a constant frictional force of 12.0 N along the slope. What is the minimum inclined angle of tilt θ before the crate starts to slide down the slope? A 0.245° B 13.9° C 14.2° D 75.8° 7 Which statement about mass and weight is true? A Weight changes with the planet’s gravitational field strength. B Mass changes with the planet’s gravitational field strength. C Mass is a vector quantity. D Weight is a scalar quantity. 8 A block o f mass 2.10 kg is attached to a light inextensible string. A constant force of 6.00 N is applied to the string in order to accelerate the block at 0.100 m / s 2 along a rough horizontal surface. The string broke off from the block and the block continues to move through a distance before coming to a stop. If the frictional force is constant, what is the acceleration of the block when the string broke? A 0 m / s2 B –0.10 m / s2 C –2.76 m / s2 D –5.79 m / s2 crate θ rough inclined slope block string 6.00 N rough horizontal surface

4 9 A wooden cube of mass 100 kg is at rest on a rough horizontal surface. The len gth of each side of the cube is 60.0 cm. The tension of the rope attached to corner X, is gradually increased in the horizontal direction. What is the minimum tension needed to tilt the cube? A 50.0 N B 100 N C 491 N D 981 N 10 Two stationary blocks X and Y are connected by a string which passes over a smooth, fixed pulley as shown in the diagram. Assume that the friction between any two surfaces is 2.0 N. If a horizontal force F is applied to block Y, what is the minimum work don e by force F to move block Y over a distance of 0.50 cm? A 1.0 x 10-2 J B 2.0 x 10-2 J C 3.0 x 10-2 J D 4.0 x 10-2 J X Y F X 60.0 cm tension

5 11 The kinetic energy of a toy car decreases from 8.0 J to 5.0 J over a period of 10.0 s. What is the average power loss of the toy car? A 0.10 W B 0.30 W C 0.50 W D 0.80 W 12 Transverse sinusoidal waves of wavelength λ are progressing along a horizontal rope. P and Q are points on the rope 0.75λ apart and the waves are travelling from P to Q. Which one of the following correctly describes Q at an instant when P is displaced downwards but moving upwards? displacement of Q movement of Q A upwards upwards B upwards downwards C downwards upwards D downwards downwards 13 The diagram shows the displacement –distance graph of air molecules at a particular instant when a sound wave passes through air. The displacement to the right is taken to be positive. Which point shows a centre of rarefaction at this instant? A point P B point Q C point R D point S displacement distance P Q R S

6 14 Solid cubes X and Y are made of the same material, but the length of one side of X is twice that of Y. Given that twice the amount of thermal energy was supplied to X as compared to Y, what is the ratio of the heat capacity of X to Y? Assume no heat loss to the surroundings. A 0.5 B 1.0 C 2.0 D 8.0 15 The diagram shows the pattern of electric field produced by three charged spheres P, Q and R. What could be the charge of the three charged spheres? charge of P charge of Q charge of R A negative negative positive B negative positive positive C positive negative negative D positive positive negative P Q R

7 16 The diagram shows an electric dipole (a positive and negative charge of equal magnitude connected by a rigid rod) placed in an electric field. Which statement is correct? A The dipole will experience no net force. B The dipole will experience a net force towards the left. C The dipole will experience a net force towards the right. D The dipole will experience a net force upwards. 17 The potential difference between the ends of a conductor is 6.0 V. How much electrical energy is converted to other forms of energy in the conductor when 60 C of charge flows through it? A 0.010 J B 10 J C 66 J D 360 J 18 Wires P and Q are made of the same material. The ratio of the mass of wire P to the mass of wire Q is 0.250. The ratio of the length of wire P to the length of wire Q is 1.25. What is the ratio of the resistance of wire P to the resistance of wire Q? A 0.200 B 1.56 C 5.00 D 6.25 electric field – q + q

8 19 The diagram shows a potential divider circuit consisting of a cell, light dependent resistor (LDR), potentiometer and a light bulb. The circuit is us ed to vary the potential difference across a light bulb. The light bulb is brightest when A light is incident on the LDR and P is moved to X. B light is incident on the LDR and P is moved to Y. C the LDR is covered and P is moved to X. D the LDR is covered and P is moved to Y. 20 The diagram shows a 3.0 Ω resistor connected in parallel to a variable resistor R1, where R1 > 3.0 Ω. Which is true about the effective resistance R? A R > 3.0 Ω B R < 3.0 Ω C R > R1 D 3.0 Ω < R < R1 R1 3.0 Ω X Y P

9 21 Which of the following is not a safety feature in an electrical system? A circuit breaker B double insulation C fuse D transformer 22 Two equally strong bar magnets are placed side by side on a table as shown in the diagram. A compass is placed ex