The largest source of background radiation in the UK is:
From Paper 2: Advanced Physics II
15(a)3 marks
Describe how absorbers can be used to identify which types of radiation a source emits.
From Paper 2: Advanced Physics II
15(b)3 marks
Technetium-99m has a half-life of 6.0 hours. A patient is injected with 400 MBq. Calculate the activity after 24 hours and the decay constant.
From Paper 2: Advanced Physics II
15(c)4 marks
Explain why nuclear fusion only happens at very high temperatures and densities, such as in the cores of stars.
From Paper 3: General and Practical Principles in Physics
7(a)4 marks
In the Sun, 4 ¹H → ⁴He + 2e⁺ + 2ν. Mass of ¹H nucleus 1.007276 u, ⁴He nucleus 4.001506 u, positron 0.000549 u. Calculate the energy released in MeV (1 u = 931.5 MeV).
From Paper 3: General and Practical Principles in Physics
7(b)3 marks
The Sun's luminosity is 3.83 × 10²⁶ W. Calculate the mass it loses each second, and explain why fusion happens only in the core.
Score 0 / 18 · 0 of 6 marked
This paper is written by Plasmo in the style of the Edexcel A-Level Physics exam. It is not a past paper and is not produced or endorsed by the exam board.