Question

How much energy do individual photons of 470 nm light have

Answer 1

Answer:

4.227 × 10^-19 Joules

Explanation:

Energy of a photon of light is calculated by the formula;

E = hf, where h is the plank's constant, 6.626 × 10^-34 J-s and f is the frequency.

But, f = c/λ

Where, c is the speed of light (2.998 × 10⁸ m/s), and λ is the wavelength.

Given the wavelength is 470 nm or 4.7 × 10^-7 m

Therefore;

E = hc/λ

  = (6.626 × 10^-34 J-s × 2.998 × 10^8 m/s) ÷ 4.7 × 10^-7 m

  = 4.227 × 10^-19 Joules

Therefore, the energy of a photon with 470 nm is 4.227 × 10^-19 Joules