Nuclear : Fundamentals

Radius of an atom (roughly)

R = 1.25A^1/3 (R in femotpmeters = 10^-15m) (~0.2nm)

Describe strong force

Strength = 10^38

Range = 10^-15m

Glue that holds nucleons together to form a nucleus

Describe weak force

Strength = 10^33

Range = 10^-18

Plays role in beta decays and enables stellar fusion

Describe electromagnetic force

Strength = 10^36

Range = infinite

Acts between charged particles

Describe gravitational force

Strength = 1

Range = infinite

Acts on objects that have mass

Radioactivity activity equation

a(t) = a0 e^(-λT(half))

Half life log equation

ln(1/2) = -λT(half)

T(half) = 0.693/λ

Rest mass equation

Relativistic kinetic energy

Define binding energy

Minimum work done against the holding forces in order to pull a nucleus apart into its constituent nucleons

• In a closed system, its equal to the energy required to combine the nucleons into a nucleus

Binding energy equation

What is conserved in a reaction?

Nucleons, charge, momentum and energy

What energy is released and recoverable from different aspects during a U-235 fission?

Fission fragments - 168MeV/168

Beta rays - 8MeV/8

Gamma rays - 7MeV/7

Neutrinos - 12MeV/0

Prompt gamma rays - 7MeV/7

Fission neutrons - 5MeV/5

Capture gamma rays - 0MeV/3-12MeV

Total = 207MeV / 198-207MeV

Nuclear stability graph