# Nature of light and electromagnetic spectrum

According to Newton’s corpuscular theory, light is propagated as a stream of particles, called corpuscules. This could justify the phenomenon of reflection and refraction of light but failed to explain the phenomenon of diffraction, interference etc. Clerk Maxwell suggested that light waves are associated with both electric and magnetic fields

i.e., light may be described as electromagnetic waves or radiations. there are three characteristics properties associated with any kind of wave.

i –  Wavelength:  is the dis­tance between the two neighboring crests or troughs of a wave. It is generally symbolized by the Greek letter lambda (l)

ii –  Frequency : is the number of waves per second. It is denoted by the Greek letter nu (ν). Its unit is cycle per second Hertz (Hz).

iii – Velocity is the distance traveled by the .wave in one second. It is denoted by the letter c and is equal. to the product of wavelength and frequency i.e.,

c = λ x ν