For Examiners Use - Materials For this paper you must have: • a p...

*JUN25 7408101*

IB/M/Jun25/G4006/E14 7408/1

For Examiner’s Use Question Mark 1 2 3 4 5 6 7 8

9–33

TOTAL

Friday 23 May 2025 Morning 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 1 / 4

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*02* IB/M/Jun25 /7408/1

Do not write outside the box Section A

Answer all questions in this section.

• 1

This question is about an isotope of titanium that only decays by electron capture.

• 1

. 1 Complete Figure 1 to show the quark change that occurs during electron capture.Label the incoming and outgoing particles and the exchange particle.[3 marks]

Figure 1

• 1

. 2 In some circumstances, a nucleus of this isotope can exist with no orbiting electrons.

Explain why a neutral atom of this isotope is less stable than a nucleus that has no orbiting electrons.[1 mark]

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3

*03* Turn over ►

IB/M/Jun25/7408/ 1

Do not write outside the box

• 1

. 3 A nucleus of this isotope of titanium has a proton number of 22 and a specific charge of 4.8 × 10 7 C kg −1 .

Determine the number of neutrons in this nucleus.[2 marks]

number of neutrons =

Turn over for the next question

6

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4

*04* IB/M/Jun25/7408/ 1

Do not write outside the box

• 2

. 1 State what is meant by a transverse wave.[2 marks]

Figure 2 shows apparatus that is used to investigate stationary waves on a stretched wire.

Figure 2

A block of weight W is used to keep the wire under tension.

The frequency of the ac supply is varied until a stationary wave is produced on the wire.

• 2

. 2 Explain how a stationary wave is produced on the wire.[1 mark]

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