Nuclear Engineering / Subcategory

Radiation

Radiation calculators and formulas for radioactive decay and half-life. Includes decay constant, activity, and remaining mass calculations for radioactive isotopes.

11Formulas

All levels Difficulty

Updated Jul 2026

← All Nuclear Engineering (96) Radiation (11)

Fundamental

Secular Equilibrium Activity Ratio

A_daughter = A_parent (at secular equilibrium)

Fundamental

Half-Value Layer

HVL = ln(2) / μ

Fundamental

Shielding Exponential Attenuation

I = I0 * e^(-μx)

Fundamental

Inverse Square Law for Radiation Intensity

I2 = I1 * (d1/d2)²

Fundamental

Absorbed Dose Rate

Ḋ = D / t

Fundamental

Radiation Dose Equivalent (Sievert)

H = D * WR

Fundamental

Curie to Becquerel Conversion

A(Bq) = A(Ci) * 3.7 * 10^10

Fundamental

Specific Activity

SA = A / m = (λ * NA) / M

Fundamental

Radioactive Activity

A = λ * N

Fundamental

Half-Life Relation

t₁/₂ = ln2 / λ

Fundamental

Radioactive Decay Law

N = N₀e^(−λt)