KCET2024PhysicsDual Nature of Matter
A galaxy is moving away from the Earth so that a spectral line at 600 nm is observed at 601 nm . Then, the speed of the galaxy with respect to the Earth is
Options
- A500 ~km ~s ⁻¹
- B50 ~km ~s ⁻¹
- C200 ~km ~s ⁻¹
- D20 ~km ~s ⁻¹
Correct answer
A. 500 ~km ~s ⁻¹
Step-by-step solution
Given, =600 ~nm =6 10⁻⁷ ~m =(601-600) 10⁻⁹ ~m =1 10⁻⁹ ~m We know that, = v c v=c =3 10^8 1 10⁻⁹ 6 10⁻⁷ = 1 2 10^6 ~m / s =500 10^3 ~m / s =500 ~km / s