Question

Suppose that Star X and Star Y both have redshifts, but Star X has a smaller redshift than Star Y. What can you conclude?

Answer 1

Red shift of star is defined as its wavelength. Star with smaller red shift have smaller wavelength, while star with greater red shift have greater wavelength. We can say that, Star X have smaller wavelength, while star Y have greater wavelength.

Answer 2

Answer:

here start X and star Y both have red shift which means they both will move away

Also star X has smaller red shift than star Y which means star X is moving slower as compare to start Y

Explanation:

When source of light move relative to an stationary observer then the change is frequency is given by the formula

$\frac{\delta nu}{\nu} = \frac{v}{c}$

also we can write it in terms of wavelength

$\frac{\Delta \lambda}{\lambda} = \frac{v}{c}$

so here if the source is moving away from the observer then the frequency of the light will decreased and hence the wavelength will increase

This effect is known as red shift and as per above formula it depends on the speed of the source

so here start X and star Y both have red shift which means they both will move away

Also star X has smaller red shift than star Y which means star X is moving slower as compare to start Y