The ratio of the wave lengths of the first line in the Lyman series of the spectrum of Hydorgen atom and the first line in the Balmer series of the spectrum of He^(+) is

The ratio of the wave lengths of the first line in the Lyman series of

1.	The ratio of the wave lengths of the first line in the Lyman series of the spectrum of Hydorgen atom and the first line in the Balmer series of the spectrum of He^(+) is
Answer» `20//27` `27//20` `27//5` `5//27` SOLUTION :`bar(upsilon) = Z^2 R [1/(1^2) - 1/(2^2)] and lambda = 1/(bar(upsilon))` `(lambda_H)/(lambda_(He^+)) = ((1)^2 (1/((1)^2) - 1/((2)^2)))/((2^2) (1/((2)^2) - 1/((3)^2))) = (27)/(5)`