Official June 2024 AQA A-level PHYSICS 7408/3BD Paper 3 Section B Turning points in physics Merged Question Paper + Mark Scheme + Insert Ace your Mocks!!! *JUN2474083BD01* IB/M/Jun24/E9 7408/3BD For Examiner’s Use Question Mark 1 2 3 4 TOTAL Monday 17 June 2024 Morning 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 35. • 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 3 Section B Turning points in physics Time allowed: The total time for both sections of this paper is 2 hours. You are advised to spend approximately 50 minutes on this section. 2 *02* IB/M/Jun24/7408/3BD Do not write outside the Section B box Answer all questions in this section. 0 1 . 1 Figure 1 shows apparatus used in an experiment to measure the specific charge of the electron. Figure 1 Electrons are accelerated by the potential difference VA. The electrons then enter the region between two parallel metal plates, shown shaded in Figure 1. The parallel metal plates are separated by a distance d with a potential difference VP across them. In the same region there is a uniform magnetic field of flux density B into the plane of the diagram. Explain why the electron beam is undeflected in the shaded region shown in Figure 1. [2 marks] Do not write outside the box 3 *03* Turn over ► IB/M/Jun24/7408/3BD Do not write outside the 0 1 box . 2 Determine, using the following data, a value for the specific charge of the electron. B = 1.59 mT VP = 1.51 kV d = 5.0 cm VA = 1.00 kV [4 marks] specific charge = C kg−1 Turn over for the next question 6 4 *04* IB/M/Jun24/7408/3BD Do not write outside the 0 2 box . 1 Figure 2 shows a cross-sectional view of the arrangement that Millikan used to determine the charge on the electron. Figure 2 Millikan’s initial step was to determine the radius of the oil droplet. Explain how Millikan used this apparatus to determine the radius of the oil droplet. In your answer you should: • describe the procedure used, the measurements taken and any additional data required • describe how the radius was determined from the measurements • state the physical principles and assumptions involved in the determination of the radius. [6 marks]