Due to transitions among its first three energy levels, hydrogenic atom emits radiation at three discrete wavelengths `lamda_(1), lamda_(2), " and " lamda_(3) (lamda_(1) lt lamda_(2) lt lamda_(3))`. Then

Options

A. `lamda_(1)= lamda_(2) + lamda_(3)`
B. `lamda_(1) + lamda_(2)= lamda_(3)`
C. `1//lamda_(1) + 4 // lamda_(2)= 1//lamda_(3)`
D. `1//lamda_(1)=1 //lamda_(2) + 1//lamda_(3)`

Answer

D

Explanation

`(hc)/(lamda_(1))= (hc)/(lamda_(2)) + (hc)/(lamda_(3)) rArr (1)/(lamda_(1)) = (1)/(lamda_(2)) + (1)/(lamda_(3))`