JEE Main202226 Jun 2022Evening ShiftPhysicsWaves and SoundActual
For a specific wavelength 670 nm of light coming from a galaxy moving with velocity v , the observed wavelength is 670 . 7 nm . The value of v is
Options
- A3 × 10 8   m   s - 1
- B3 . 13 × 10 5   m   s - 1
- C3 × 10 10   m   s - 1
- D4 . 48 × 10 5   m   s - 1
Correct answer
B. 3 . 13 × 10 5   m   s - 1
Step-by-step solution
The apparent change in the wavelength is given by Δ λ λ = v c ⇒ v = c Δ λ λ = 3 × 10 8 × 670 . 7 - 670 670 = 3 . 13 × 10 5   m   s - 1 Hence, velocity of the planet is 3 . 13 × 10 5   m   s - 1 .