Physics 9702/13 October/November 2019: question paper and mark scheme

Question

Which quantity with its unit is correct? A acceleration of a bicycle = 1.4 m s–1 B electric current in a lamp = 0.25 A s–1 C electric potential difference across a battery = 8.0 J C–1 D kinetic energy of a car = 4500 N m–1

Question

Which two units are not equivalent to each other? A N m and kg m2 s–2 B N s and kg m s–1 C J s–1 and kg m2 s–3 D Pa and kg m s–2

Question

The arrow represents a vector R. Which diagram does not represent R as two perpendicular components? A B C D

Question

What could reduce systematic errors? A averaging a large number of measurements B careful calibration of measuring instruments C reducing the sample size D repeating measurements 2

Question

The power loss P in a resistor is calculated using the formula P = V . R The percentage uncertainty in the potential difference V is 3% and the percentage uncertainty in the resistance R is 2%. What is the percentage uncertainty in P ? A 4% B 7% C 8% D 11%

Question

A lead sphere is released from rest at point X, a long way above the surface of a planet. The sphere falls in a vacuum. After a time of 4.0 s, it has fallen through a vertical distance of 3.0 m. Assume the acceleration of free fall is constant. How far will the sphere have fallen from point X at a time of 20 s after its release? A 15 m B 75 m C 80 m D 2000 m

Question

A box rests on the Earth, as shown. Newton’s third law describes how forces of the same type act in pairs. One of the forces of a pair is the weight W of the box. Which arrow represents the other force of this pair? B box D not to W scale C A Earth

Question

A snowflake is falling from the sky on a still day. Its weight acts vertically downwards and air resistance acts vertically upwards. As the snowflake falls, air resistance increases until it is equal to the weight and there is no resultant force acting on the snowflake. air resistance weight When the forces become equal, which statement is correct? A The snowflake accelerates. B The snowflake decelerates. C The snowflake is stationary. D The snowflake moves at a constant velocity.

Question

Two objects X and Y in an isolated system undergo a perfectly elastic collision. The velocities of the objects before and after the collision are shown. 20 m s–1 12 m s–1 10 m s–1 v X Y X Y before after collision collision What is the speed v of Y after the collision? A 2.0 m s–1 B 18 m s–1 C 22 m s–1 D 24 m s–1

Question

A solid sphere, which is less dense than water, is held completely immersed in water a few metres below the surface. The density of the water is uniform. The sphere is released. Immediately after release, the sphere rises. Which row correctly describes the changes in the upthrust on the sphere and the resultant force on the sphere? upthrust on resultant force the sphere on the sphere A constant increasing B constant decreasing C decreasing increasing D decreasing decreasing

Question

The diagram shows two pairs X and Y of parallel forces. X Y 20 N 40 N 50 cm 50 cm 40 N 20 N Which statement is correct? A X is equivalent to a clockwise torque of 10 N m and a force of 20 N to the left. B X is equivalent to a clockwise torque of 20 N m only. C Y is equivalent to an anticlockwise torque of 30 N m and a force of 20 N to the left. D Y is equivalent to an anticlockwise torque of 30 N m only.

Question

A heavy ball hanging from a cable is held in equilibrium by a chain, as shown. point of suspension cable chain heavy ball Which vector diagram shows the three forces acting on the ball? A B tension tension in cable in cable weight weight of ball of ball tension tension in chain in chain C D tension weight tension weight in cable of ball in cable of ball tension tension in chain in chain

Question

At sea level, atmospheric pressure is 100 kPa and the density of air is 1.3 kg m–3. Assume that the density of air decreases linearly with height above sea level. What is an estimate of the total height of the atmosphere based on this information? A 7.8 km B 16 km C 77 km D 150 km

Question

Trains supply coal to a power station. The table shows quantities describing the operation of the power station. symbol unit power station average output P W number of trains per day N mass of coal on a train M kg energy from 1 kg of coal E J number of seconds in one day S Which expression gives the efficiency of the power station? A PS B PSN C NME D NM NME ME PS PSE

Question

A piston in a gas supply pump has an area of 500 cm2 and it moves a distance of 30 cm. The pump moves the gas against a fixed pressure of 4000 Pa. How much work is done by the piston? A 60 J B 6.0 × 103 J C 6.0 × 105 J D 6.0 × 107 J

Question

A steel ball is falling at constant speed in oil. Which graph shows the variation with time of the gravitational potential energy Ep and the kinetic energy Ek of the ball? A B energy energy Ek Ek Ep Ep 0 time 0 time C D Ek Ek energy energy Ep Ep 0 time 0 time

Question

The maximum useful output power of a car travelling on a horizontal road is P. The total resistive force acting on the car is kv2, where v is the speed of the car and k is a constant. Which equation is correct when the car is travelling at maximum speed? 2 3     A v3 = P B v2 = P C v = P  D v = P  k k k k

Question

Initially, four identical uniform blocks, each of mass m and thickness h, are spread on a table. h h The acceleration of free fall is g. How much work is done on the blocks in stacking them on top of one another? A 3 mgh B 6 mgh C 8 mgh D 10 mgh

Question

The stress–strain graph for a wire is shown. stress / 108 Pa 2.1 0 0 1.4 strain / 10–3 What is the Young modulus of the material of the wire? A 6.7 × 10–12 Pa B 6.7 × 10–9 Pa C 1.5 × 108 Pa D 1.5 × 1011 Pa

Question

The diagram shows a force–extension graph for a rubber band as the band is extended and then the stretching force is decreased to zero. force rubber band extends rubber band contracts 0 0 extension What can be deduced from the graph? A The rubber band does not return to its original length when the force is decreased to zero. B The rubber band obeys Hooke’s law for the extensions shown. C The rubber band remains elastic for the extensions shown. D The shaded area represents the work done in extending the rubber band.

Question

Which statement about light waves and sound waves is not correct? A Light waves and sound waves can both demonstrate the Doppler effect. B Light waves are transverse waves and sound waves are longitudinal waves. C Light waves can be diffracted but sound waves cannot. D Light waves can travel in a vacuum but sound waves cannot.

Question

The graph represents a sound wave. 3 displacement / µm 0 0 5 10 15 20 25 30 35 40 45 50 55 time / ms –3 Which statement is correct? A The wave is longitudinal and has a period of 25 ms. B The wave is longitudinal and has a frequency of 50 Hz. C The wave is transverse and has an amplitude of 3 µm. D The wave is transverse and has a wavelength of 20 ms.

Question

A cathode-ray oscilloscope (CRO) is used to display a wave of frequency 5.0 kHz. The display is shown. 1 cm 1 cm What is the time-base setting of the CRO? A 10 µs cm–1 B 100 µs cm–1 C 10 ms cm–1 D 100 ms cm–1

Question

A siren emits sound of frequency 1000 Hz. The siren moves at 20 m s–1 towards an observer who is standing still. The speed of sound in the air is 330 m s–1. Which expression would correctly give the frequency heard by the observer? 1000 × 330 A 330 + 20 1000 × 330 B 330 − 20 1000 (330 + 20) C 330 1000 (330 − 20) D 330

Question

A source of sound of constant power P is situated in an open space. The intensity I of sound at distance r from this source is given by I= P . 4πr 2 How does the amplitude a of the vibrating air molecules vary with the distance r from the source? A a∝ 1 B a ∝ 12 C a∝r D a ∝ r2 r r

Question

In an experiment to demonstrate a stationary wave, two microwave transmitters, emitting waves of wavelength 4 cm, are set facing each other, as shown. transmitter transmitter d detector A detector is moved along a straight line between the transmitters. It detects positions of maximum and minimum signal. The detector is a distance d from the left-hand transmitter. Assume that both transmitters are at antinodes of the stationary wave. Which row gives a value of d for a maximum and for a minimum? value of d for value of d for a maximum / cm a minimum / cm A 46 48 B 47 48 C 48 47 D 49 47

Question

The graph shows how the height of the water surface at a point in a harbour varies with time t as waves pass the point. height p mean height t q What are p and q? p q A displacement period B displacement wavelength C amplitude period D amplitude wavelength

Question

The diagram shows a sketch of a wave pattern over a short period of time. 1.0 m Which description of this wave is correct? A The wave is longitudinal, has a wavelength of 20 cm and is stationary. B The wave is transverse, has a wavelength of 20 cm and is stationary. C The wave is transverse, has a wavelength of 40 cm and is progressive. D The wave is transverse, has a wavelength of 40 cm and is stationary.

Question

The double-slit experiment demonstrates interference between two coherent sources of light waves. In the diagram, the curved lines represent wavefronts. At which point does complete destructive interference (a minimum) occur? A C B D single slit double slit

Question

Light of wavelength 567 nm is incident normally on a diffraction grating. The grating has 400 lines per mm. A number of diffraction maxima are observed on the far side of the grating. What is the angle between the second-order maximum and the third-order maximum? A 13.1° B 13.9° C 15.9° D 27.0°

Question

The diagram shows the electric field pattern between two opposite and unequal point charges P and Q. P Q Which statement about the charges is correct? A P is negatively charged and has a smaller charge than Q. B P is negatively charged and has a greater charge than Q. C P is positively charged and has a smaller charge than Q. D P is positively charged and has a greater charge than Q.

Question

A uniform electric field is represented by five horizontal field lines. P Q P and Q are two points in the field. The field causes a positively charged particle in a vacuum to move from P to Q. Which statement must be correct? A The acceleration of the particle between P and Q is increasing. B The kinetic energy of the particle at P is the same as the kinetic energy of the particle at Q. C The force on the particle at Q is greater than the force on the particle at P. D Work is done on the particle as it moves from P to Q.

Question

A metal electrical conductor has a resistance of 5.6 kΩ. A potential difference (p.d.) of 9.0 V is applied across its ends. How many electrons pass a point in the conductor in one minute? A 6.0 × 1020 B 1.0 × 1019 C 6.0 × 1017 D 1.0 × 1016

Question

A battery of electromotive force (e.m.f.) 12 V and negligible internal resistance is connected to three resistors, each of resistance 6.0 Ω, as shown. 6.0 Ω 6.0 Ω 6.0 Ω R 12 V What is the power dissipated in resistor R? A 2.7 W B 6.0 W C 11 W D 24 W

Question

A box containing two electrical components is connected into a circuit. V box A The variable resistor is adjusted and measurements are taken to determine the I–V characteristic for the box, as shown. I 0 0 V Which arrangement of two electrical components in the box would create the best fit to the measured I–V characteristic? A a filament lamp and a fixed resistor in parallel B a filament lamp and a fixed resistor in series C a semiconductor diode and a filament lamp in parallel D a semiconductor diode and a filament lamp in series

Question

A cell of internal resistance 0.5 Ω is connected to a fixed resistor of resistance 10 Ω. The resistance of the resistor is changed to 20 Ω. Which statement is not correct? A The current in the circuit will halve. B The e.m.f. of the cell will remain constant. C The power dissipated by the fixed resistor will decrease. D The terminal p.d. of the cell will increase.

Question

Which row correctly describes Kirchhoff’s laws? physics principle physics principle Kirchhoff’s first law applied for first Kirchhoff’s second law applied for law second law A The sum of the conservation The sum of the e.m.f.s conservation currents entering a of charge around any closed loop of energy junction equals the in a circuit equals the sum of the currents sum of the p.d.s around leaving the junction. the same loop. B The sum of the conservation The sum of the e.m.f.s conservation currents entering a of energy around any closed loop of charge junction equals the in a circuit equals the sum of the currents sum of the p.d.s around leaving the junction. the same loop. C The sum of the e.m.f.s conservation The sum of the currents conservation around any closed of energy entering a junction of charge loop in a circuit equals equals the sum of the the sum of the p.d.s currents leaving the around the same loop. junction. D The sum of the e.m.f.s conservation The sum of the currents conservation around any closed of charge entering a junction of energy loop in a circuit equals equals the sum of the the sum of the p.d.s currents leaving the around the same loop. junction.

Question

In the circuit shown, all the resistors are identical. V4 V V V1 V2 V V V3 The reading V1 is 8.0 V and the reading V2 is 1.0 V. What are the readings on the other voltmeters? V3 / V V4 / V A 1.5 1.0 B 3.0 2.0 C 4.5 3.0 D 6.0 4.0

Question

A radioactive nucleus emits an α-particle or a β– particle, creating a product nucleus. Which decay could create the product nucleus stated? radioactive nucleus decay product nucleus 226 224 A 88 Ra α 86 Rn 238 242 B 92 U α 94 Pu 228 C 88 Ra β– 228 87 Fr 231 D 90Th β– 231 91Pa

Question

Which statement is correct? A Electrons and neutrinos are fundamental particles. B Electrons and neutrinos are hadrons. C Protons and neutrons are leptons. D Protons and neutrons are quarks.