Edexcel A-Level Physics 2027 Predicted Practice Paper — Paper 3

Answer ALL questions. Write your answers in the spaces provided. You must write down all the stages in your working.

Section A

Short-answer and structured questions. Answer ALL questions.

• 1

  Question SECTION-A1 (7 marks)

  A satellite of mass 640 kg orbits a planet in a circular orbit of radius 8.20 x 10^6 m. The planet has mass 4.87 x 10^24 kg. (a) State what provides the centripetal force on the satellite. (1 mark) (b) Show that the orbital speed of the satellite is about 6.3 x 10^3 m s^-1. Use G = 6.67 x 10^-11 N m^2 kg^-2. (3 marks) (c) Calculate the period of the orbit, giving your answer in hours. (3 marks)

  (Total for Question SECTION-A1 is 7 marks)
• 2

  Question SECTION-A2 (7 marks)

  A capacitor of capacitance 470 microfarad is charged to a potential difference of 12.0 V and then discharged through a fixed resistor of resistance 22 kilo-ohm. (a) Calculate the initial charge stored on the capacitor. (2 marks) (b) Calculate the time constant of the discharge circuit. (2 marks) (c) Calculate the potential difference across the capacitor 5.0 s after discharge begins. (3 marks)

  (Total for Question SECTION-A2 is 7 marks)
• 3

  Question SECTION-A3 (6 marks)

  A body of mass 0.25 kg oscillates with simple harmonic motion on a spring. The amplitude of oscillation is 0.080 m and the period is 0.90 s. (a) Define simple harmonic motion. (2 marks) (b) Calculate the maximum speed of the body. (2 marks) (c) Calculate the maximum kinetic energy of the body. (2 marks)

  (Total for Question SECTION-A3 is 6 marks)
• 4

  Question SECTION-A4 (7 marks)

  A straight wire of length 0.15 m carries a current of 4.0 A. It is placed at right angles to a uniform magnetic field of flux density 0.35 T. (a) Calculate the magnitude of the force on the wire. (2 marks) (b) State the direction rule used to find the direction of this force and name the quantities each finger represents. (2 marks) (c) The wire is now rotated so that it makes an angle of 30 degrees to the field lines. Calculate the new force on the wire. (3 marks)

  (Total for Question SECTION-A4 is 7 marks)
• 5

  Question SECTION-A5 (8 marks)

  In a nuclear reactor, a nucleus of uranium-235 absorbs a slow neutron and undergoes fission. (a) Explain what is meant by binding energy per nucleon. (2 marks) (b) The binding energy per nucleon of uranium-235 is 7.59 MeV and the mean binding energy per nucleon of the fission fragments is 8.45 MeV. The total number of nucleons is conserved at 236 (including the absorbed neutron). Estimate the energy released per fission, in MeV. (3 marks) (c) Convert this energy to joules. Use 1 MeV = 1.60 x 10^-13 J. (3 marks)

  (Total for Question SECTION-A5 is 8 marks)
• 6

  Question SECTION-A6 (7 marks)

  A transformer is used to step down mains voltage. The primary coil has 2400 turns connected to a 230 V a.c. supply, and the secondary coil delivers 11.5 V. (a) Calculate the number of turns on the secondary coil. (2 marks) (b) The transformer is 96% efficient and delivers a power of 46 W to a load. Calculate the current drawn from the 230 V supply. (3 marks) (c) State two causes of energy loss in a real transformer. (2 marks)

  (Total for Question SECTION-A6 is 7 marks)
• 7

  Question SECTION-A7 (7 marks)

  Two point charges are placed 0.30 m apart in a vacuum. Charge A is +4.0 nC and charge B is -6.0 nC. (a) Calculate the magnitude of the electrostatic force between the charges. Use k = 8.99 x 10^9 N m^2 C^-2. (3 marks) (b) State whether the force is attractive or repulsive, and justify your answer. (2 marks) (c) State what happens to the magnitude of the force if the separation is doubled. (2 marks)

  (Total for Question SECTION-A7 is 7 marks)
• 8

  Question SECTION-A8 (8 marks)

  A photon of light of wavelength 4.50 x 10^-7 m is incident on a clean metal surface with a work function of 2.10 eV. (a) State what is meant by the work function of a metal. (1 mark) (b) Calculate the energy of the incident photon in joules. Use h = 6.63 x 10^-34 J s and c = 3.00 x 10^8 m s^-1. (3 marks) (c) Determine whether a photoelectron will be emitted, and if so calculate its maximum kinetic energy in joules. Use 1 eV = 1.60 x 10^-19 J. (4 marks)

  (Total for Question SECTION-A8 is 8 marks)
• 9

  Question SECTION-A9 (6 marks)

  A gas is contained in a sealed rigid cylinder. Its temperature is raised from 27 degrees C to 227 degrees C. (a) State the assumption about the gas that allows the ideal gas law to be applied. (1 mark) (b) The initial pressure of the gas is 1.0 x 10^5 Pa. Calculate the final pressure, explaining your method. (3 marks) (c) Explain, in terms of molecular motion, why the pressure changes. (2 marks)

  (Total for Question SECTION-A9 is 6 marks)
• 10

  Question SECTION-A10 (7 marks)

  A coil of 150 turns and cross-sectional area 2.5 x 10^-3 m^2 is placed with its plane perpendicular to a magnetic field. The flux density increases uniformly from 0.10 T to 0.40 T in a time of 0.20 s. (a) State Faraday's law of electromagnetic induction. (2 marks) (b) Calculate the magnitude of the average e.m.f. induced in the coil. (3 marks) (c) State Lenz's law and explain how it is consistent with conservation of energy. (2 marks)

  (Total for Question SECTION-A10 is 7 marks)
• 11

  Question SECTION-A11 (7 marks)

  A radioactive source containing 8.0 x 10^12 undecayed nuclei has a half-life of 6.0 hours. (a) Define the decay constant of a radioactive isotope. (1 mark) (b) Calculate the decay constant in s^-1. (3 marks) (c) Calculate the activity of the source at the start, in becquerel. (3 marks)

  (Total for Question SECTION-A11 is 7 marks)
• 12

  Question SECTION-A12 (8 marks)

  A proton is accelerated from rest through a potential difference of 2.0 x 10^6 V. (a) Calculate the kinetic energy gained by the proton, in joules. Charge of proton = 1.60 x 10^-19 C. (2 marks) (b) Calculate the final speed of the proton. Mass of proton = 1.67 x 10^-27 kg. (3 marks) (c) The proton then enters a uniform magnetic field of flux density 0.50 T at right angles to its velocity. Calculate the radius of its circular path. (3 marks)

  (Total for Question SECTION-A12 is 8 marks)

Section B

Synoptic and extended response questions. Answer ALL questions.

• 1

  Question SECTION-B1 (12 marks)

  A rollercoaster car of total mass 480 kg travels around a vertical circular loop of radius 7.5 m. At the top of the loop the car moves at 9.0 m s^-1. Use g = 9.81 m s^-2. (a) Explain why the car must have a minimum speed at the top of the loop to maintain contact with the track, and derive an expression for this minimum speed. (4 marks) (b) Calculate the minimum speed at the top of this loop and state whether the car is travelling fast enough. (3 marks) (c) At the top of the loop, calculate the actual force exerted by the track on the car at 9.0 m s^-1. (3 marks) (d) Discuss one reason why the speed of the car at the bottom of the loop is greater than at the top, referring to energy. (2 marks)

  (Total for Question SECTION-B1 is 12 marks)
• 2

  Question SECTION-B2 (11 marks)

  A student investigates the discharge of a 2200 microfarad capacitor through a 15 kilo-ohm resistor. The capacitor is initially charged to 9.0 V. (a) Sketch and describe the shape of the graph of potential difference across the capacitor against time during discharge, and state how the time constant can be found from it. (4 marks) (b) Calculate the time taken for the potential difference to fall to half its initial value. (4 marks) (c) The student wants the discharge to be slower. Explain two separate changes to the circuit that would increase the time constant, and state the effect of each on the time constant quantitatively. (3 marks)

  (Total for Question SECTION-B2 is 11 marks)
• 3

  Question SECTION-B3 (12 marks)

  In a particle physics experiment, a stationary neutral pion (rest energy 135 MeV) decays into two photons of equal energy. Separately, an alpha particle of mass 6.64 x 10^-27 kg and speed 1.5 x 10^7 m s^-1 collides head-on and sticks to a stationary lithium nucleus of mass 1.16 x 10^-26 kg. (a) For the pion decay, state and apply the principle of conservation of momentum to explain why the two photons must travel in opposite directions with equal energy. (3 marks) (b) Calculate the energy, in MeV, of each photon produced in the pion decay. (2 marks) (c) For the collision, calculate the speed of the combined mass immediately after the collision, stating the conservation principle used. (4 marks) (d) Explain whether the collision is elastic or inelastic and justify your answer. (3 marks)

  (Total for Question SECTION-B3 is 12 marks)