IB DP Physics Mock Exam SL Paper 1B Set 2 - 2025 Syllabus
IB DP Physics Mock Exam SL Paper 1B Set 2
Prepare for the IB DP Physics Mock Exam SL Paper 1B Set 2 with our comprehensive mock exam set 2. Test your knowledge and understanding of key concepts with challenging questions covering all essential topics. Identify areas for improvement and boost your confidence for the real exam
Question
(a) Radioactive decay is said to be “random” and “spontaneous”. Outline what is meant by
Random:. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Spontaneous: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . each of these terms. [2]
(b) A stationary nucleus of uranium-238 undergoes alpha decay to form thorium-234.
The following data are available.
Energy released in decay 4.27
MeV Binding energy per nucleon for helium 7.07 MeV
Binding energy per nucleon for thorium 7.60 MeV
(i) Calculate the binding energy per nucleon for uranium-238. [3]
(ii) Calculate the ratio 
[2]
Answer/Explanation
Ans:
a random: it cannot be predicted which nucleus will decay
OR
it cannot be predicted when a nucleus will decay
spontaneous: the decay cannot be influenced/modified in any way
b i 234× 7.6
OR
4× 7.07 BEU= « 234 × 7.6 + 4 × 7.07 – 4.27 = » 1802 « MeV » \(\frac{BE}{A}\) = «\(\frac{1802}{238}\) = » 7.57 « MeV »
b ii states or applies conservation of momentum ratio is