Question

please answer this question with explanation

Answer 1

The energy emitted depends on the shell no...E is proportional to 1/n^2As each transition is from n=4 to n =2.. all emit the same energy..D)

Answer 2

First reason :

As H-atom contence only one electron.the energy of H-atom depends on the energy of electron . these energy decreases when electron changes its position from high level to lower level then some energy is emitted .this emitted energy is in form of photon.

The wavelength of a photon is depends on the energy difference from high energy level to low energy level .if the energy difference is greater then the wavelength of emitted photon is minimum by the equetion E=hc| lamda
Second reason : 

The energy emitted depends on the shell no...

E is proportional to 1/n^2As each transition is from n=4 to n =2.. all emit the same energy..D) 
hope this helps you