If a source of light is moving away from a stationary observer,then the frequency of light wave appears to change because of

$A$ star moves away from Earth at a speed of $0.8 c$ while emitting light of frequency $6 \times 10^{14} \text{ Hz}$. What frequency will be observed on the Earth (in units of $10^{14} \text{ Hz}$)? ($c$ is the speed of light)

Due to the Doppler effect, the shift in wavelength observed is $0.1 \text{ Å}$ for a star producing a wavelength of $6000 \text{ Å}$. The velocity of recession of the star will be: (in $\text{ km/s}$)

The Doppler effect is applicable for

The time period of rotation of the sun is $25$ days and its radius is $7 \times 10^8 \ m$. The Doppler shift for the light of wavelength $6000 \ \mathring{A}$ emitted from the surface of the sun will be ...... $\mathring{A}$.

If a star emitting light of wavelength $5000\,\mathring{A}$ is moving towards Earth with a velocity of $1.5 \times 10^6\,\text{m/s}$,then the shift in the wavelength due to Doppler's effect will be......$\mathring{A}$