Question

The speed of electromagnetic wave in vacuum depends upon the source of radiation. It

• A. increases as we move from $\gamma$-rays to radio waves
• B. decreases as we move from $\gamma$-rays to radio waves
• C. is same for all of them
• D. None of these

Answer 1

Answer: (C)

is same for all of them

$Answer:-$ C

speed of electromagnetic wave in vacuum is given by:-

c(speed of light)=frequency$\times$ wavelength =$\frac{1}{{\mu }_0{ϵ}_0}$=constant

as we go from gamma rays to radio waves frequency decreases and wavelength increases thereby maintaining the product constant.