Review Of Radiation Physics

Question 1

Mass of the particle when it is not moving

Answer 1

Rest Mass

Question 2

Measure of how strongly the particle is attracted to an electrical field, and can either be positive or negative

Answer 2

Electric Charge

Question 3

Spontaneous disintegration of atomic nuclei

Answer 3

Radioactivity

Question 4

Process whereby an excited, unstable nucleus dropped into state of lower energy stability

Answer 4

Radioactivity

Question 5

Standard unit of radioactivity

Answer 5

Curie

Question 6

Measure of the number of disintegrations occurring one gram of radium per second

Answer 6

Curie

Question 7

Time required to decay one-half of the initial number of atoms
Time required for the initial activity to decrease by one-half

Answer 7

Half-life

Question 8

Emitted by materials found in nature that is naturally radioactive and unstable

Answer 8

Natural Radioactivity

Question 9

Emitted by materials which is a product of nuclear reaction initiated by man

Answer 9

Artificial Radioactivity

Question 10

Modes of Decay

Answer 10

Alpha Particle Emission
Beta Particle Emission
Gamma Emission

Question 11

Emitted from the nucleus of an atom as unstable nuclei undergo decay

Answer 11

Gamma emission

Question 12

Mainly dependent on the wavelength of radiation and therefore its energy
Dependent on the density, thickness and atomic number of interacting material

Answer 12

Radiation interaction

Question 13

Incident electron loses a small amount of energy to the nucleus of atom and bounce away with reduced energy

Answer 13

Elastic collision

Question 14

High energy electron pass close to the nucleus and be strongly attracted that they will slow down and change direction losing some of their kinetic energy

Answer 14

Inelastic collision

Question 15

Progressive weakening of an X-ray beam

Answer 15

Attenuation

Question 16

Reduction in the energy involves process of

Answer 16

Absorption
Scattering
Combination

Question 17

Transfer of energy from the primary X-ray beam to the atom in which the X-ray beam interacts as it passes through the medium

Answer 17

Absorption

Question 18

Occurs following collisional interaction bet the primary X-ray beam and atoms of the medium

Answer 18

Scattering

Question 19

Photon retains much of its energy

Answer 19

Forward direction

Question 20

Photon lost much of its energy

Answer 20

Back scatter

Question 21

Thickness of some material required to reduce the wan intensity to half of its original value

Answer 21

Half Value Layer

Question 22

High HVL

High penetrating ability

Answer 22

Hard beam

Question 23

Low HVL
Low penetrating ability
Deposit their energy in a medium fairly quickly

Answer 23

Soft Beam

Question 24

Composed of different energy levels of radiation

Answer 24

Polyenergetic beam

Question 25

Smallest unit of matter

Answer 25

Atom