The wavelength is nothing but the length of a wave. The wavelength of light will be so small that it is expressed in nanometers (nm). In the modern physics its accepted that the light has a dual nature. Sometimes it acts as mass less particles and the other times as waves. If light is taken as a wave, the visible light has several colors having its own wavelength slightly varying from other that determines other properties of the light wave like frequency, speed etc.
Wavelength of a wave. |

$\lambda$ = $\frac{c}{f}$

Since the speed of light is constant (c = 3 $\times$ 108 m/s).

Hence, the formula is

$\lambda$ = $\frac{3 \times 10^8\ m/s}{f}$where f is the frequency of light.

The frequency varies from violet to red. Hence the wavelength varies depending on its frequency.

The visible spectrum of light comprises of following colors: Violet, Indigo, Blue, Green, Yellow, Orange, Red has known as VIBGYOR. It corresponds to the wavelength range of 400-700 nm. It varies from shortest to longest wavelength. The white light is composed of all these colors present in the visible spectrum.

Light Color |
Wavelength |

Violet | 390 - 420 |

Indigo | 420 - 455 |

Blue | 455 - 492 |

Green | 492 - 577 |

Yellow | 577 - 597 |

Orange | 597 - 622 |

Red | 622 - 780 |

**Lets see some examples on how to calculate the wavelength of light:**

### Solved Examples

**Question 1:**A light wave has frequency of 6.23 $\times$ $10^{14}$

^{}Hz. Calculate its wavelength and determine in which color it lies in the spectrum.

**Solution:**

Given:

Frequency of wave = 6.23 $\times$ $10^{14}$

^{}Hz

The wavelength of light wave is given by,

Wavelength $\lambda$ = $\frac{3 \times 10^8\ m/s}{6.23 \times 10^14}$

= 481 nm

**Question 2:**Calculate the frequency if the wavelength of wave is 660 nm.

**Solution:**

Given:

Wavelength of wave $\lambda$ = 660 nm

The frequency of light wave is given by,

Frequency f = $\frac{3 \times 10^8\ m/s}{\lambda}$

= $\frac{3 \times 10^8\ m/s}{660 \times 10^-9\ m}$

= 4.5 $\times$ $10^{14}$

^{}Hz.