An observer is moving with half the speed of light towards a stationary microwave source emitting waves at frequency 10 GHz. What is the frequency of the microwave measured by the observer ? (Speed of light `=3xx10^(8)ms^(-1))`

Options

A. `17.3` GHz
B. `15.3` GHz
C. `10.1` GHz
D. `12.1` GHz

Answer

A

Explanation

`f_(1)=f_(s)xx sqrt((1+beta)/(1-beta))`
`=fxxx sqrt((1+(1)/(2))/(1-(1)/(2))) " " [ :. beta=(v)/(c)=(1)/(2)]`
`=fsxxsqrt(((3)/(2))/((1)/2))`
`=10 xx sqrt(3)`
`=10xx1.73`
`=17.3 GHz`