Nuclear Physics

Question 1

Alpha

Answer 1

Strong, slow
Stopped by paper and few cm air
Alpha particle released (4,2) so decrease mass by 4 and atomic by 2

Question 2

Beta

Answer 2

Minus:

Weak,fast
Stopped by 3mm aluminium
Mass no is same, atomic no up by 1

Plus:
Annihilated by electron, no range
Mass no is same, atomic no down by 1

Question 3

Gamma

Answer 3

Weak, speed of light
Stopped by lead/ few m of concrete
Energy released as photon, no change in number

Question 4

Fission

Answer 4

Heavy nuclei split
Add neutron, split = atoms, neutrons, energy
Chain reaction

Question 5

Fusion

Answer 5

2 light nuclei combine

Energy and atom released

Question 6

Fission reactor

Answer 6

U-235 = fuel rods
Neutrons slowed down = thermal neutrons 
Moderator = water, slows them down 
Critical mass = mass of fuel to cause chain reaction 
Control rods = boron, absorb neutrons
Coolant = water, remove heat

Question 7

Carbon Decay

Answer 7

When organism dies: C-12 stops being taken in, C-14 decays

Ratio of C-14 to C-12 in artefact compared with living ratio determines age

Question 8

Decay constant

Answer 8

Probability of decay of nucleus per unit time

Question 9

Activity

Answer 9

Rate of nuclei decay