# Photon and colour of light

1. Jun 14, 2006

### gaurav pant

i have read that light is made up of photons :rofl: how does similar photons can produce lights of different colours(pardon me if this appears a silly question to u

2. Jun 14, 2006

### Staff: Mentor

The color of a photon depends on its wavelength $\lambda$ or frequency $f$ or energy $E$ (take your pick). They're all related to each other:

$$c = \lambda f$$

$$E = hf$$

$$E = hc / \lambda$$

where $c$ is the speed of light and $h$ is Planck's constant.