De Broglie Wavelength Calculator
⚛ Modern physics. Use the de Broglie wavelength formula to find wavelength λ, mass, speed: pick the value you want, type the others, and the answer updates as you go.
Moving particles behave like waves too.
Pick the ○ next to the value you want to find, fill in the others, and it solves as you type.
What each letter means
| Quantity | Unit |
|---|---|
| Wavelength λ | m |
| Mass | kg |
| Speed | m/s |
Worked example
Find the wavelength λ when Mass = 9.109 × 10⁻³¹ kg, Speed = 1 × 10⁶ m/s.
Using λ = h/mv: Wavelength λ = 7.27 × 10⁻¹⁰ m.
Frequently asked questions
What is the formula for de Broglie wavelength?
λ = h/mv. Moving particles behave like waves too.
What do the letters stand for, and what units are used?
Wavelength λ in m, Mass in kg, Speed in m/s.
How do you calculate wavelength λ?
Put the values into λ = h/mv. For example, with Mass = 9.109 × 10⁻³¹ kg, Speed = 1 × 10⁶ m/s, wavelength λ = 7.27 × 10⁻¹⁰ m.
Can I solve for a different value?
Yes. In the calculator above, pick the circle next to any value (wavelength λ, mass, speed) and fill in the others: it rearranges the formula for you.
