In hydrogen, the transition from level 2 to level 1 has a rest wavelength of 121. 6 nm.


1). Find the speed for a star in which this line appears at wavelength 120. 4 nm.


2). Find the direction for a star in which this line appears at wavelength 120. 4 nm.


3). Find the speed for a star in which this line appears at wavelength 121. 4 nm.


4). Find the direction for a star in which this line appears at wavelength 121. 4 nm


5). Find the speed for a star in which this line appears at wavelength 122. 2 nm.


6. Find the direction for a star in which this line appears at wavelength 122. 2 nm


7). Find the speed for a star in which this line appears at wavelength 122. 9 nm.


8). Find the direction for a star in which this line appears at wavelength 122. 9 nm.



Answer :