A star is moving towards the earth with a speed of 4.5 xx 10^(6) m/s.If the true wavelength of a certain line in the spectrum received from the star is 5890 Å, its apparent wavelength will be about [ c = 3 xx 10^(5) m/s].

A star is moving towards the earth with a speed of 4.5 xx 10^(6) m/s.I

1.	A star is moving towards the earth with a speed of 4.5 xx 10^(6) m/s.If the true wavelength of a certain line in the spectrum received from the star is 5890 Å, its apparent wavelength will be about [ c = 3 xx 10^(5) m/s].
Answer» `5890 Å` `5978 Å` `5802 Å` `5896 Å` Solution :`lambda. = lambda(1 -(V)/(c)) = 5890 (1 - (4.5 xx 10^(6)))/(3 xx 10^(8)) approx 5802 Å`

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A star is moving towards the earth with a speed of 4.5 xx 10^(6) m/s.If the true wavelength of a certain line in the spectrum received from the star is 5890 Å, its apparent wavelength will be about [ c = 3 xx 10^(5) m/s].

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