A-Level PhysicsYear 2021Q2
4 2 A student used a Geiger-Müller (GM) tube to determine the activity of a radium source. Radium emits α, β, and γ radiation. He positioned the source 20 cm from the GM tube, as shown, and recorded the count for 1 minute. He repeated the measurement and calculated a mean count. GM tube radium source The student recorded the following results. Count 1 Count 2 Mean count 183 178 181 (a) Criticise the student’s method for determining the count at this position. (3) .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. Turn over 5 (b) From his results the student determined that the activity of the source was 3.0 Bq. Comment on his value for the activity of the source. (5) .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. (Total for Question 2 = 8 marks)
Paper Source:9PH0_03_que_20211021.pdf
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Exam Specification Info
This question is part of the UK A-Level Physics syllabus. In the actual exam, structured questions typically require linking specific keywords to gain full marks. Applaa helps you drill these topics.
Syllabus levelAdvanced Level (A-Level)
SubjectPhysics
Official MarksVariable (2–6 marks)
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