Question

How to calculate the energy of a photon?

Answer 1

The energy of a photon can be calculated in two ways:

1. If the photon's frequency $f$ is known, we can use the formula $E=hf$. Max Planck proposed this equation, which is why it is known as Planck's equation.
2. If the photon's wavelength is known, the photon's energy can be calculated using the formula $E=\frac{hc}{\lambda }$ . $h$is planck's constant, $c$ is the speed of light, and $\lambda$ is the wavelength of the radiation are all represented in the equation.

Hence, we can calculate the energy of photon by using either $E=hf$ or $E=\frac{hc}{\lambda }$.