Nuclear Calculators

Interactive tools for nuclear physics calculations

Use these calculators to verify your hand calculations and build computational speed. Understanding the logic is more important than the result.

Calculate remaining nuclei after given time using N(t) = N₀ e^(-λt)

Initial Number of Nuclei (N₀)

Time Elapsed (t) in seconds

Decay Constant (λ) in s⁻¹

When to use this: Any problem asking "How many nuclei remain after time t?" or "What fraction has decayed?"

Calculate binding energy and BE/A from atomic mass

Mass Number (A)

Atomic Number (Z)

Atomic Mass (in u)

Logic: Mass defect = [Z×mₚ + N×mₙ] - M_atomic. Then multiply by 931.5 to get BE in MeV. This is the energy needed to break nucleus apart.

Calculate energy released/absorbed in nuclear reactions

Total Mass of Reactants (in u)

Total Mass of Products (in u)

Common Error: Mixing up reactants and products. Q = (reactants - products) × 931.5. If Q > 0, energy is released.

Convert between T½, λ, and τ

Half-Life (T½)

Time Unit

Total Time Elapsed

Half-Life Duration

Calculate activity from number of nuclei and decay constant

Number of Nuclei (N)

Decay Constant (λ) in s⁻¹

Remember: Activity A = λN. It decays exponentially like N: A(t) = A₀ e^(-λt). Units: 1 Curie = 3.7 × 10¹⁰ Bq.