What is the actual wavelength of light (in `mum` ) emitted by the fixed star towards which the earth is moving with a velocity of `30 Kms^(-1)`? Given an observer on the earth observes a shift of `0.58 Å` in the wavelength of light coming from the star.

Answer

`00.58`

Explanation

Using, `Delta lamda = (v)/(c) lamda`
Here `v = 30 kms ^(-1) = 3 xx 10 ^(4) ms ^(-1)`
` c =3 xx 10 ^(8) ms ^(-1)`
`Delta lamda = 0.58 xx 10 ^(-10) m`
` therefore lamda =( c)/(v) Delta lamda `
`= ( 3 xx 10 ^(8))/( 3 xx 10 ^(4)) xx 0. 58 xx 10 ^(-10) m`
`= 0. 58 xx 10 ^(-6) m`
`= 0. 58 mu m`