Question

What is the energy of one photon of red light that has a wavelength of 678 nm?

Answer 1

Answer:

E = 2.93×10⁻¹⁹ J

Explanation:

Given data:

Wavelength of photon = 678 nm   (678×10⁻⁹ m)

Energy of photon = ?

Solution:

Formula:

E = h c/λ

h = 6.63×10⁻³⁴ Js

c = 3×10⁸ m/s

E = 6.63×10⁻³⁴ Js × 3×10⁸ m/s / 678×10⁻⁹ m

E = 19.89 ×10⁻²⁶ Jm / 678×10⁻⁹ m

E = 0.0293×10⁻¹⁷ J

E = 2.93×10⁻¹⁹ J