hello,
what is wavelength? we say it in terms of meters. but it is dependent of frequency. please explain clearly.

 

How about this?

http://www.techterms.com/definition/wavelength

 

This paragraph taken from the article in this link is incorrect.

http://www.techterms.com/definition/wavelength

Waves in the electromagnetic spectrum, such as radio waves and light waves, have much shorter wavelengths than sound waves. Therefore, these wavelengths are typically measured in millimeters or nanometers, rather than centimeters or meters.

EM waves travel at the speed of light, c = 3x10^8 m/s.

The frequency range spans 20 orders of magnitude.

Using the equation

λ = c/f

you can calculate the wavelength λ.

The wavelength of the EM signal from an FM station transmitting at 100MHz is 3 metres.
The wavelength of the EM signal from an AM station transmitting at 1000kHz is 300 metres.