Question
Question: A free nucleus of mass 24 amu emits a gamma photon (when initially at rest). The energy of the photo...
A free nucleus of mass 24 amu emits a gamma photon (when initially at rest). The energy of the photon is 7 Mev. The recoil energy of the nucleus in KeV is –
A
2.2
B
3.1
C
22
D
1.1
Answer
1.1
Explanation
Solution
Conserving linear momentum
1 amu = 931 MeV = 1.67 × 10–27 kg
p = 
KE = 
̃ KE = 1.1 KeV