If the shift of wavelength of light emitted by a star is towards the violet end of the spectrum,then this shows that the star is

The periodic time of rotation of a certain star is $22$ days and its radius is $7 \times 10^8 \ m$. If the wavelength of light emitted by its surface is $4320 \ \mathring{A}$, the Doppler shift will be $(1 \ day = 86400 \ s)$

$A$ rocket is moving away from the Earth at a speed of $10^{6} \ m/s$. If the wavelength of the light wave emitted by it is $5700 \ \mathring{A}$,what will be its Doppler shift in $\mathring{A}$?

$A$ star is moving away from the Earth. An observer on the Earth will see the wavelength of light coming from the star as:

$A$ rocket is moving towards the moon with a speed $v$. The astronaut in the rocket sends signals of frequency $f$ towards the moon and receives them back after reflection from the moon. What will be the frequency of the signal received by the astronaut? (Assume $v << c$)

$A$ rocket is moving away from the earth at a speed of $6 \times 10^7 \ m/s$. The rocket has blue light in it. What will be the wavelength of light recorded by an observer on the earth in $\mathring A$? (Wavelength of blue light $\lambda = 4600 \ \mathring A$)