Unit 1&2 - Nuclear Physics

Question 1

What is an isotope?

Answer 1

Atoms of the same element with different numbers of neutrons in their nucleus. e.g. 1H 2H(Deutrium) 3H(Tritium)

Question 2

What is an alpha particle?

Hint: Atom formation

Answer 2

4
He
2

Question 3

What is a Beta particle?

Hint: Atom formation

Answer 3

0
e
-1

Question 4

What is a Gamma Photon?

Hint: Atom formation

Answer 4

0
loopy ring
0

Question 5

What is radioactive decay?

Answer 5

When an unstable nuclei in some materials break up, or disintegrate.

Question 6

What is activity and what unit is activity represented in?

Answer 6

Activity: In a radioactive sample the average number of disintegration per second.
Unit: Bequerel (Bq)
e.g. 100 Bq = 100 nuclei disintegrating per second.

Question 7

What is half life?

Answer 7

The time taken for half of the active atoms in a radioactive sample to decay or become inactive.

Question 8

What is the half life equation?

Answer 8

N=No(1/2)^n
N: amount left or activity after time t
No: Starting amount or activity
n: Number of decays=time of the event/half life

Question 9

What is radiation dosage and the equation?

Answer 9

Exposure to radiation
AD=E/m
AD: Absorbed dose (Grays(gy)=J/kg)
E: energy exposed to (J)
m: mass of the person (kg)

Question 10

What is quality factor and what are the values of a, b & g particles?

Answer 10

The ionising ability of particles.

a=20 b=1 g=1

Question 11

What is dose equivalent and what is the equation?

Answer 11

How much radiation that is exposed taking into account the type of radiation.
DE=AD x QF
DE: Dose equivalent (Sieverts(Sv))
AD: Absorbed dose (Gy)
QF: Quality factor

Question 12

What is binding energy?

Answer 12

The amount of energy holding a nucleus together.

Question 13

How do you figure out binding energy?

Answer 13

(Mass of protons + mass of nuetrons) - Mass of nucleus = Mass difference (Binding energy in mass)

Question 14

What is nuclear fission?

Answer 14

A reaction in which a heavy nuclide captures a neutron and then splits into smaller radioactive nuclides with the release of energy.

Question 15

What is the process of nuclear fission?

Answer 15

Neutron –> Mother nuclei = Daughter nuclei(s) + speeding neutrons

Question 16

What is the penetrating power of an alpha particle?

Answer 16

Low

Question 17

What is the penetrating power of a Beta particle?

Answer 17

Medium

Question 18

What is the penetrating power of a gamma photon?

Answer 18

High

Question 19

What is nuclear fusion?

Answer 19

The combining of smaller nuclei to form a larger nucleus.

Question 20

What does the Moderator do in a nuclear reactor?

Answer 20

Slows fast neutrons to enable the capturing of Uranium 235. Heavy water (uses 2 H 1)

Question 21

What does the Coolant do in a nuclear reactor?

Answer 21

Removes heat from the core and is used to produce steam as a heat exchanger.

Question 22

What is the fuel for a nuclear reactor?

Answer 22

Uranium 235 rods

Question 23

How is the process inside a nuclear reactor controlled?

Answer 23

Using rods of Cadmium or Boron, these rods are raised or lowered to speed up or slow down the reactions. When the rods are lowered, excess neutrons are absorbed to control the fission reactions.

Question 24

What are three uses of radiation?

Answer 24

Industry: used to control the thickness of materials in manufacturing
Smoke detectors
Food irradiation: passes through item killing any bacteria
Radio carbon dating: - calculating the age of organic material
Medicine: Treatments such as radiology
Kills unwanted tissue
Tracers for diagnosis