Question

How many photons are produced in a laser pulse of 0.364 J at 477 nm?

Answer 1

Answer:

1.00 × 10¹⁸

Explanation:

1. Calculate the energy of one photon

The formula for the energy of a photon is

E = hc/λ  

h = 6.626 × 10⁻³⁴ J·s; c = 2.998 × 10⁸ m·s⁻¹

λ = 477 nm = 477 × 10⁻⁹ m                              Insert the values

E = (6.626 × 10⁻³⁴ × 2.998× 10⁸)/(477 × 10⁻⁹)

E = 4.165× 10⁻¹⁹ J

2. Calculate the number of photons

Divide the total energy by the energy of one photon.

No. of photons = 0.418 × 1/4.165 × 10⁻¹⁹      

No. of photons = 1.00 × 10¹⁸