AQA A-level PHYSICS 7408/1 Paper 1 Version: 1.0 Final *JUN* IB/M/Jun23/E8 7408/1// QUESTION PAPER & MARKING SCHEME/ [MERGED] Marl( scheme June 2023

AQA A-level PHYSICS 7408/1 Paper 1 Version: 1.0 Final *JUN* IB/M/Jun23/E8 7408/1 For Examiner’s Use Question Mark 1 2 3 4 5 6 7–31 TOTAL Wednesday 24 May 2023 Afternoon Time allowed: 2 hours Materials For this paper you must have: • a pencil and a ruler • a scientific calculator • a Data and Formulae Booklet • a protractor. Instructions • Use black ink or black ball-point pen. • Fill in the boxes at the top of this page. • Answer all questions. • You must answer the questions in the spaces provided. Do not write outside the box around each page or on blank pages. • If you need extra space for your answer(s), use the lined pages at the end of this book. Write the question number against your answer(s). • Do all rough work in this book. Cross through any work you do not want to be marked. • Show all your working. Information • The marks for questions are shown in brackets. • The maximum mark for this paper is 85. • You are expected to use a scientific calculator where appropriate. • A Data and Formulae Booklet is provided as a loose insert. Please write clearly in block capitals. Centre number Candidate number Surname Forename(s) Candidate signature I declare this is my own work. A-level PHYSICS Paper 1 2 *02* IB/M/Jun23/7408/1 Section A Answer all questions in this section. 0 1 The neutral lambda particle Λ0 is a baryon with a strangeness of −1 One possible decay for a Λ0 is 0 0 Λ→π +n 0 1 . 1 Deduce the quark structure of a Λ0 . [1 mark] 0 1 . 2 State and explain which interaction is involved in this decay. [2 marks] 0 1 . 3 An antiparticle of the neutral lambda particle decays into a neutral pion and particle X. Identify X. [1 mark] Do not write outside the box 3 *03* Turn over ► IB/M/Jun23/7408/1 Do not write outside the 0 1 box . 4 The rest energy of a Λ0 is equal to the energy of a photon with a frequency of 2.69 × 1023 Hz. Determine, in MeV, the rest energy of a Λ0 . [1 mark] rest energy = MeV 0 1 . 5 The discovery of particles such as the Λ0 is made by large international research teams. Suggest one reason for this. [1 mark] Turn over for the next question 6 4 *04* IB/M/Jun23/7408/1 Do not write outside the There are no questions printed on this page box DO NOT WRITE ON THIS PAGE ANSWER IN THE SPACES PROVIDED 5 *05* Turn over ► IB/M/Jun23/7408/1 Do not write outside the 0 2 box In 2021 the world land speed record was 1230 km h−1 . This was the average speed achieved by a jet-powered car in two runs. Each run was measured over a distance of 1.61 km. 0 2 . 1 The average speed for one of these runs was 343 m s−1 . Calculate, in s, the time taken for the car to complete the other run. [2 marks] time = s Question 2 continues on the next page 6 *06* IB/M/Jun23/7408/1 Do not write outside the 0 2 box . 2 Engineers are designing a new jet-powered car to break this record. Figure 1 shows the variation of speed with distance for the car, as predicted by the engineers. Figure 1 The car reaches its maximum acceleration when it is 5600 m from the start. At this point the mass of the car is 6.50 × 103 kg. Determine the kinetic energy of the car at its maximum acceleration. [2 marks] kinetic energy = J 7 *07* Turn over ► IB/M/Jun23/7408/1 Do not write outside the 0 2 box . 3 At any point on the graph in Figure 1, the acceleration is given by: acceleration = speed × gradient of line When the car is at its maximum acceleration, the power input to the jet engines is 640 MW. Calculate the percentage of the input power used to accelerate the car at its maximum acceleration. [4 marks] percentage of input power = % 0 2 . 4 Scientists recommend that the average deceleration of the driver of the car should be less than 3g. Deduce whether the average deceleration is less than 3g. [2 marks] 10 8 *08* IB/M/Jun23/7408/1 Do not write outside the There are no questions printed on this page box DO NOT WRITE ON THIS PAGE ANSWER IN THE SPACES PROVIDED 9 *09* Turn over ► IB/M/Jun23/7408/1 Do not write outside the 0 3 box . 1 In Figure 2 the cell has emf ε and internal resistance r. Figure 2 The current in the circuit is I. The potential difference (pd) across R1 is V1 and the pd across R2 is V2. Explain how the law of conservation of energy applies in this circuit. You should consider the movement of one coulomb of charge around the circuit. [2 marks] Question 3 continues on the next page 10 *10* IB/M/Jun23/7408/1 Do not write outside the box Figure 3 shows a variable resistor made with a thin conducting layer on an insulating base. Figure 3 The conducting layer has constant width and thickness and has connections at the ends A and B. C is a sliding contact that can move along the surface of the conducting layer between A and B. Figure 4 shows a circuit that uses the variable resistor as a potential divider. Figure 4 The variable resistor is connected to a battery of emf 3.00 V and internal resistance r. The resistance of the conducting layer between A and B is 125 Ω. 11 *11* Turn over ► IB/M/Jun23/7408/1 Do not write outside the 0 3 box . 2 The sliding contact C is moved to end B of the variable resistor. The switch is closed. The digital voltmeter reads 2.89 V. Show that r is approximately 4.8