1. Which orbital electron has the least binding energy?

a) M shell
b) N shell
c) K shell
d) L shell

2. The radius of a nucleus is how much smaller than that of an atom?

a) 100 times
b) 1000 times
c) 10000 times
d) 100000 times

3. Nuclear binding energies are usually expressed in units of:

a) eV
b) Joules
c) KeV
d) MeV

4. The Hydrogen-3 nucleus (also called Tritium) consists of:

a) Two neutrons and one proton
b) Two neutrons and no protons
c) Two neutrons and two protons
d) Two protons and one neutron

5. Which one of the following is a nucleon?

a) Proton
b) Molecule
c) Electron
d) Positron

6. For nuclear stability:

a) A is directly proportional to Z
b) A is proportional to Z square
c) A binding energy of at least 931.48 MeV is required
d) The number of protons must exceed the number of neutrons

7. Gamma-ray photons have:

a) No mass and an electric charge of +1
b) No mass and an electric charge of -1
c) No mass and no electric charge
d) No mass and an electric charge of +2

8. Positron Emission involves the ejection of:

a) A proton and a neutron
b) A beta-plus particle
c) An alpha-particle
d) A beta-minus particle

9. Electron Capture involves:

a) An electron combining with a neutron
b) An electron combining with a proton
c) A neutron being ejected from the nucleus
d) An electron being ejected from the nucleus

10. In Positron Emission:

a) Z decreases by 1 and A remains the same
b) Z remains the same and A decreases by 1
c) Z remains the same and A increases by 1
d) Z increases by 1 and A remains the same

11. In Alpha Decay:

a) Z decreases by 4 and A decreases by 4
b) Z decreases by 2 and A decreases by 4
c) Z decreases by 4 and A decreases by 2
d) A & Z will remain same

12. Electron Emission involves the ejection of:

a) A proton and a neutron
b) A beta-plus particle
c) An alpha-particle
d) A beta-minus particle

13. Isomeric Transition involves:

a) Conversion of a neutron to a proton
b) Conversion of a proton to a neutron
c) Emission of a gamma-ray
d) K-capture

14. Internal Conversion involves:

a) The conversion of a neutron to a proton
b) The emission of a gamma-ray
c) K-capture
d) None of the above

15. In spontaneous fission:

a) The nucleus is unchanged
b) The nucleus splits into 2 or 3 fragments
c) Nuclear stability is always achieved
d) The fragments are never radioactive

16. An alpha-particle consists of:

a) Two protons and two neutrons
b) Two protons and one neutron
c) One proton and one neutron
d) One proton and two neutrons

17. The Half-Life of 99m-Tc is 6 hours. After how much time will one-eighth of the radioactivity in a sample remain?

a) 6 hrs
b) 16 hrs
c) 18 hrs
d) 12 hrs

18. 1 MBq is equal to:

a) 37 thousand, million curies
b) 1 decay per second
c) 1 billion decays per second
d) 1 million decays per second

19. The Radioactive Decay Law is expressed by:

a) A linear function
b) A logarithmic function
c) An exponential function
d) A sinusoidal function

20. When the Decay Constant increases:

a) The Half Life decreases
b) The Half Life increases
c) First the half-life increases and then decreases
d) The Half Life remains unchanged