Total marks: 58 · Duration: 1 hour 15 minutes · Tier: Higher
Instructions to candidates
• Answer all questions. • Use black ink or black ball-point pen. • The number of marks is given in brackets [ ] at the end of each question or part question. • Show all your working in calculations; credit may be given for a correct method. • The equations you need are standard GCSE physics equations; any values required are given in the questions. • The total number of marks for this paper is 58. • All the data and tables you need are printed within the questions.
Paper
Section A — Structured Questions (42 marks)
1. Electricity
(a) State the equation that links charge, current and time, and give the unit of charge. [2]
(b) A current of 3 A flows through a lamp for 2 minutes. Calculate the charge that flows. [3]
(c) The lamp has a potential difference of 12 V across it. Calculate the power of the lamp and the energy it transfers in the 2 minutes. [4]
2. Energy and efficiency
(a) A motor is supplied with 800 J of electrical energy and transfers 600 J as useful kinetic energy. Calculate the efficiency of the motor. [2]
(b) State what happens to the energy that is not usefully transferred. [1]
(c) Explain two ways in which the design of an appliance could be changed to make it more energy efficient. [3]
(d) Describe one advantage and one disadvantage of generating electricity using wind power rather than fossil fuels. [2]
3. Forces and motion
(a) State the difference between speed and velocity. [2]
(b) A car accelerates uniformly from 8 m/s to 20 m/s in 6 seconds. Calculate its acceleration. [3]
(c) The car has a mass of 1200 kg. Calculate the resultant force needed to produce this acceleration, and explain what happens to the braking distance if the car is travelling faster. [4]
4. Waves
(a) State the difference between a transverse and a longitudinal wave, giving an example of each. [3]
(b) A wave has a frequency of 50 Hz and a wavelength of 6 m. Calculate its speed. [2]
(c) Explain what happens to a wave when it passes from one medium into another and changes speed, and name this effect. [3]
5. Radioactivity
(a) Describe the structure of an atom in terms of the particles it contains and where they are found. [3]
(b) State what is meant by the half-life of a radioactive isotope. [2]
(c) A sample contains 800 undecayed nuclei of an isotope with a half-life of 5 days. Calculate how many undecayed nuclei remain after 15 days, and explain your method. [3]
Section B — Extended Response (16 marks)
6. Electricity is transmitted across the country through the National Grid at very high voltages using transformers.
(a) Explain why electricity is transmitted at a high voltage rather than a low voltage. [4]
(b) Explain the difference between a step-up and a step-down transformer, and state where each is used in the National Grid. [4]
(c) A step-up transformer has 100 turns on the primary coil and 5000 turns on the secondary coil. The primary voltage is 240 V. Calculate the secondary (output) voltage. [2]
7. Describe the life cycle of a star that is about the same size as the Sun, from its formation to the end of its life. [6]