A star is moving away from earth with velocity of 100 km s- 1 . If the velocity of light is 3× 108 m s- 1 , then shift of the spectral line of λ =5700 Å due to Doppler effect will be

Question

A star is moving away from earth with velocity of 100 km s- 1 . If the velocity of light is 3× 108 m s- 1 , then shift of the spectral line of λ =5700 Å due to Doppler effect will be (A) 1.90 Å (B) 3.80 Å (C) 5.70 Å (D) None of these

Tardigrade Admin · Accepted Answer

In case of Dopplers effect in light waves Using Δ λ =( upsilon/c)× λ =(105 × 5700/3 × 108)=1.90 â« Δ λ = shift to spectral line

Q. A star is moving away from earth with velocity of $100 km s^{- 1}$ . If the velocity of light is $3 \times 1 0^{8} m s^{- 1}$ , then shift of the spectral line of $λ = 5700 Å$ due to Doppler effect will be

$1.90 Å$

$3.80 Å$

$5.70 Å$

None of these

In case of Dopplers effect in light waves
Using $Δ λ = \frac{υ}{c} \times λ = \frac{1 0 ^{5} \times 5700}{3 \times 1 0 ^{8}} = 1.90 Å$
$Δ λ =$ shift to spectral line

Q. A star is moving away from earth with velocity of 100kms−1 . If the velocity of light is 3×108ms−1 , then shift of the spectral line of λ=5700Å due to Doppler effect will be

1.90Å

3.80Å

5.70Å