Before the discovery of the neutron it was proposed that

Question

1. Before the discovery of the neutron, it was proposed that the penetrating radiation produced when beryllium was bombarded with α particles consisted of high-energy γ rays (up to 50 MeV) produced in reactions such as α +⁹Be →¹³ C+ γ.

(a) Calculate the Q value for this reaction.

(b) If 5-MeV α particles are incident on ⁹ Be, calculate the energy of the ¹³C nucleus and, hence, determine the energy of γ radiation assuming it is emitted as a single photon.

Hint: You may neglect the momentum of the γ ray relative to the ¹³C nucleus (see Problem 1.2). Masses: m(⁴He) = 4.0026 u, m(⁹Be) = 9.0122 u, m(¹³C)= 13.0034 u.

2. Assuming that a nucleus is ak le_yis_of nuclear matter of radius 1.2 x A 113 fm, express - the average nuclear density in SI units.