Equations · equation

Radioactive Decay Law

Nuclear Physics · 1902

Equation: N(t) = N₀·e^(−λt)
Field: Nuclear Physics
Named After: Ernest Rutherford · Frederick Soddy
Year: 1902

Symbols

N(t) undecayed nuclei remaining at time t · N₀ the starting number · λ decay constant (each nuclide's characteristic rate) · e base of natural logarithms

Significance

Each nucleus decays at random, yet a large collection empties on an exact exponential schedule — perfect statistical order out of pure chance. Discovered by Rutherford and Soddy while unravelling what radioactivity actually is: atoms of one element transmuting into another.

Minerals

Carnotite Monazite Torbernite Autunite Zircon

Timeline

Big Bang Nucleosynthesis Proton Decay, If It Happens

Theories

Nuclear Shell Model

Machines

Radioisotope Thermoelectric Generator Chicago Pile-1 Pressurized Water Reactor

Related

Half-Life Seebeck Effect Mass–Energy Equivalence Heat Equation Newton's Law of Cooling

Requires

Spectral Types

M-type Stars

Required By

Elements

Uranium Thorium Radon Radium Polonium

Referenced by

element

Polonium Radium Radon Thorium Uranium

equation

Derivative Half-Life Heat Equation Mass–Energy Equivalence Newton's Law of Cooling Seebeck Effect

event

Big Bang Nucleosynthesis Proton Decay, If It Happens

machine

Chicago Pile-1 Pressurized Water Reactor Radioisotope Thermoelectric Generator

theory

Nuclear Shell Model

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From the Equations database in Notion, last edited 2026-08-18. This page is the row, rendered by the build; nothing on it is written by hand.