1. How many electrons are contained in \(_{92}^{238}\)U nucleus?

2. Chadwick was awarded the Nobel prize in Physics in 1935 for his discovery of:

3. The density of a nucleus is of the order of:

4. When the mass of a sample of a radioactive substance decreases, the mean life of the sample:

5. Alpha particle emitted from a radioactive material are:

6. The half life of a radioactive decay is n times its mean life, n is equal to:

7. Rutherford is the unit of:

8. According to Yukawa's theory of nuclear forces, the origin of nuclear force between nucleons is due to the exchange of

9. An electron and a positron each having a mass equivalent to 0.53 MeV annihilate each other and produce a photon. The minimum energy of the photon is.

10. The wavelength of y-rays is of the order of: