What is the minimum energy that must be given to a H atom in ground state so that it can emit an line in Balmer series. If the angular momentum of the system is conserved, what would be the angular momentum of such photon?
corresponds to Balmer series transition from n=5 to n=2. Now the electron of ground state requires energy for moving to 5th orbit from 1st orbit.
Energy at n=1,
Energy at n=5,
∴ energy required =
Now if the momentum is conserved, we know that, angular momentum for electron in nth orbit is given as,
Initial momentum = final momentum
Momentum of electron in 5th orbit
= Momentum of electron in 2nd orbit+ momentum of photon
∴ the momentum of the photon released =
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