Total marks: 100 · Duration: 105 minutes · Tier: Higher
Instructions to candidates
- Use black ink or black ball-point pen. Draw diagrams in pencil.
- Answer all questions in the spaces provided.
- In all calculations, show clearly how you work out your answer.
- You may use a calculator.
- Where a question describes a graph, a diagram or apparatus in words, you may find it helpful to sketch it.
Information
- The maximum mark for this paper is 100.
- The marks for questions are shown in brackets.
- You are expected to use good English and to organise information clearly, especially in questions marked with an asterisk (*).
- This paper covers AQA GCSE Physics topics 4.5 to 4.8: forces; waves; magnetism and electromagnetism; and space physics.
- Take the gravitational field strength on Earth g = 9.8 N/kg. The speed of electromagnetic waves in a vacuum is 3.0 × 10⁸ m/s.
- Equations you may need that are on the AQA Physics equations sheet: (final velocity)² − (initial velocity)² = 2 × acceleration × distance; force = change in momentum ÷ time taken; force on a conductor = magnetic flux density × current × length; Vp ÷ Vs = np ÷ ns; Vp × Ip = Vs × Is; elastic potential energy = ½ × spring constant × (extension)².
Paper
Question 1 — Motion and stopping (14 marks)
(a) A car of mass 1000 kg has a driving force of 800 N and a total resistive force of 300 N.
(i) Calculate the resultant force on the car. [1 mark]
(ii) Calculate the acceleration of the car. [2 marks]
(b) A car accelerates uniformly from rest to 20 m/s in 8.0 s. It then travels at a constant 20 m/s for 12 s. Calculate the total distance travelled. [3 marks]
(c) The car, travelling at 20 m/s, brakes with a constant deceleration of 5.0 m/s². Calculate its braking distance. [3 marks]
(d) (i) The driver's reaction time is 0.60 s. Calculate the thinking distance and the total stopping distance at 20 m/s. [2 marks]
(ii) Give one factor that would increase the driver's reaction time. [1 mark]
(e) A book rests on a table. State the force that forms a Newton's third law pair with the weight of the book. [2 marks]
Question 2 — Momentum (10 marks)
(a) Calculate the momentum of a 1200 kg car travelling at 15 m/s. Give the unit. [2 marks]
(b) The car collides with a stationary 800 kg car. The two cars move off together. Calculate their velocity just after the collision. [3 marks]
(c) In the collision, a 70 kg passenger travelling at 15 m/s is brought to rest by an airbag in 0.15 s.
(i) Calculate the average force on the passenger. [3 marks]
(ii) Explain how the airbag reduces the risk of injury. [2 marks]
Question 3 — Forces in action (10 marks)
(a)* A skydiver jumps from a hovering helicopter. After some time, she opens her parachute and later lands safely.
Explain how the forces on the skydiver, and her velocity, change from the moment she jumps until just before she lands. [6 marks]
(b) The skydiver has a weight of 800 N. State the size of the air resistance on her when she falls at terminal velocity. [1 mark]
(c) A force of 40 N is applied at right angles to the end of a spanner, 0.25 m from the pivot. Calculate the moment of the force. [2 marks]
(d) The gravitational field strength on the Moon is 1.6 N/kg. Calculate the weight of a 70 kg astronaut on the Moon. [1 mark]
Question 4 — Pressure in fluids (8 marks)
(a) Calculate the pressure due to the water at a depth of 5.0 m in a lake. (Density of water = 1000 kg/m³) [2 marks]
(b) Explain why an object submerged in water experiences an upthrust. [3 marks]
(c) Explain why atmospheric pressure decreases as height above the Earth's surface increases. [3 marks]
Question 5 — Waves (14 marks)
(a) A sound wave has a frequency of 500 Hz and a wavelength of 0.68 m. Calculate its speed. [2 marks]
(b) Describe how a student could use a ripple tank to measure the wavelength and the frequency of water waves. [4 marks]
(c) Explain, in terms of wavefronts, why light changes direction when it enters glass at an angle. [2 marks]
(d) Give one use of ultraviolet radiation and one danger of excessive exposure to it. [2 marks]
(e) A radio station broadcasts on a wavelength of 1500 m. Calculate the frequency. [2 marks]
(f) An ultrasound pulse travels at 1540 m/s in body tissue. The echo from a boundary returns 0.00013 s after the pulse was sent. Calculate the depth of the boundary. [2 marks]
Question 6 — Light (8 marks)
(a) A converging lens forms an image 6.0 cm tall of an object 2.0 cm tall. Calculate the magnification. [2 marks]
(b) Explain why a red object appears black when it is lit only by blue light. [2 marks]
(c) Explain how the temperature of the Earth stays roughly constant, in terms of the radiation it absorbs and emits. [2 marks]
(d) Describe the difference between specular reflection and diffuse reflection. [2 marks]
Question 7 — Magnetism and electromagnetism (16 marks)
(a) Describe the magnetic field around a long straight wire carrying a current. [2 marks]
(b) A wire 0.15 m long carries a current of 3.0 A at right angles to a magnetic field of flux density 0.20 T.
(i) Calculate the force on the wire. [2 marks]
(ii) Name the rule used to find the direction of this force. [1 mark]
(c) Explain how a simple d.c. motor keeps rotating in the same direction. [3 marks]
(d) A transformer has 2000 turns on its primary coil and 100 turns on its secondary coil. The primary coil is connected to a 230 V supply.
(i) Calculate the potential difference across the secondary coil. [2 marks]
(ii) The current in the secondary coil is 2.0 A. Assuming the transformer is 100% efficient, calculate the current in the primary coil. [2 marks]
(e) Give two ways of increasing the potential difference induced when a magnet is moved into a coil. [2 marks]
(f) Explain how a loudspeaker uses the motor effect to produce sound. [2 marks]
Question 8 — Space physics (10 marks)
(a)* Describe the life cycle of a star with about the same mass as the Sun, from its formation until the end of its life. [6 marks]
(b) A satellite moves in a circular orbit at a constant speed. Explain why its velocity is changing. [2 marks]
(c) Explain how red-shift provides evidence for the Big Bang theory. [2 marks]
Question 9 — Investigating a spring (10 marks)
A student hangs weights on a spring and measures the extension.
| Force (N) | 0 | 1.0 | 2.0 | 3.0 | 4.0 | 5.0 | 6.0 |
|---|---|---|---|---|---|---|---|
| Extension (cm) | 0 | 2.0 | 4.0 | 6.0 | 8.0 | 10.6 | 14.0 |
(a) State the force at which the spring reaches its limit of proportionality. Give a reason. [1 mark]
(b) Calculate the spring constant in N/m. [2 marks]
(c) Calculate the elastic potential energy stored when the force is 3.0 N. [2 marks]
(d) Explain why the student should read the position of the pointer with their eye level with it. [1 mark]
(e) Identify the independent variable and the dependent variable. [2 marks]
(f) Give one reason for repeating the readings. [1 mark]
(g) Suggest one way to make the extension readings more precise. [1 mark]