Answer:
Step-by-step explanation:
Lightning is seen before the thunder is heard because , velocity of light exceeds velocity of sound. We also know that velocity , wavelength and frequency are related as follows
velocity = frequency x wavelength
velocity of light > velocity of sound
frequency of light x wavelength of light > frequency of sound x wavelength of sound
But given wavelength of light = wavelength of sound
Putting this relation in the equation above
frequency of light x wavelength of light > frequency of sound x wavelength of light
cancelling out equal terms on both sides
frequency of light > frequency of sound
frequency of light will be greater than frequency of sound.