Light Equations & E = MC²

Explore the fundamental equations of light and discover how they merge to reveal one of physics' most famous formulas

Interactive Parameters
Adjust these values to see how all equations are interconnected
500.00 THz
600.0 nm

Photon Energy (E)

3.31 × 10⁻¹⁹ J

2.07 eV

Photon Momentum (p)

1.10 × 10⁻²⁷ kg·m/s

Wave Equation
Speed of light equals wavelength times frequency

c = λf

Current Values:

c =299.79 × 10⁶ m/s
λ =600.0 nm
f =500.00 THz
Planck-Einstein Relation
Energy of a photon equals Planck constant times frequency

E = hf

Current Values:

E =3.31 × 10⁻¹⁹ J
h =6.63 × 10⁻³⁴ J·s
f =500.00 THz
de Broglie Relation
Momentum of a photon equals Planck constant divided by wavelength

p = h/λ

Current Values:

p =1.10 × 10⁻²⁷ kg·m/s
h =6.63 × 10⁻³⁴ J·s
λ =600.0 nm
Energy-Momentum Relation
For massless particles (photons), energy equals momentum times speed of light

E = pc

Current Values:

E =3.31 × 10⁻¹⁹ J
p =1.10 × 10⁻²⁷ kg·m/s
c =299.79 × 10⁶ m/s

All equations are interconnected through fundamental constants

c = 3.00 × 10⁸ m/s | h = 6.63 × 10⁻³⁴ J·s