Time Dilation:

Δt = Δt₀/√(1 – v²/c²)

where Δt = dilated time

Δt₀ = proper time

v = relative velocity

c = speed of light

Length Contraction:

L = L₀√(1 – v²/c²)

where L = contracted length

L₀ = proper length

v = relative velocity

c = speed of light

Relativistic Mass:

m = m₀/√(1 – v²/c²)

where m = relativistic mass

m₀ = rest mass

v = velocity

c = speed of light

Rest Mass Energy:

E₀ = m₀c²

where E₀ = rest energy

m₀ = rest mass

c = speed of light