Atomic and Nuclear Physics Answers

A radioactive material A ( decay constant A) decays into a material B( decay constant B) and into material C ( decay constant C) which is also radioactive. Determine the amount of C material remaining after a time t.

An electric field E can pull an electron out of a Helium atom in the same time that the electron takes

to go around the nucleus once. Then E is?

An atom has 3 protons and 3 neutrons. What is the atomic number?

An unwary physicist accidentally ingests radioactive sample that is both an alpha emitter (RBEα = 20) and a gamma emitter (RBE = 1).


The 75 kg physicist absorbs 3 J of energy in the form of alpha particles and 10 J of energy in the form of gamma rays.


What is the total dose equivalent in rem that the physicist has been exposed to?

You have a radioactive sample which has an activity of 3.89E5 Bq at t = 0 s. Later on at t = 1540 s you measure the activity again and find it is 3.15E5 Bq.


What is the half-life of the sample? (to 3 s.f and in s)

Calculate the Fermi energy of sodium at 0 K if it has one free electron per

atom and density 970 kg/m3 and atomic weight 23.

What is tokamak? How it is used? what are the conditions behind this invension? Describe i its future prospects?

What velocity would a 60 kg person need to move at in order to have the same momentum as a 600 nm photon?

The B−(negative) meson is the lightest particle consisting of a b quark and u antiquark. Which type of interaction causes its decay.?Describe with explanation its decay chain.

write selection rules for semi-leptonic and non-leptonic week decays.discuss by using examples and Feynman diagram?