Kinetic Energy of neutron and electron

AI Thread Summary
The discussion centers on a textbook problem involving the kinetic energies of an electron and a neutron that share the same de Broglie wavelength. Despite both particles being subjected to light of the same energy, their kinetic energies differ significantly, with values of 4.34 µeV for the electron and 0.236 neV for the neutron. The mathematical analysis indicates that their momenta must be equal, leading to a kinetic energy ratio of 2000:1, reflecting their mass difference. The confusion arises from the assumption that both particles absorb the same energy, which is not the case in this context. The thread emphasizes the distinction between logical reasoning and mathematical outcomes in physics problems.
Dexter Neutron
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Question in my textbook:-
The wavelength of light from the spectral emmision line of sodium is 589 nm.
Find the kinetic energies of electron and neutron at which they both have same de broglie wavelength.

Logically, since light of same energy is falling on both then their kinetic energies must be same thus single answer, but there are two answers given(4.34 ueV, 0.236neV).How could their kinetic energies be different if they are absorbing the same amount of energy?

Mathematically equating the de Broglie wavelength of both gives the relation that momentum of both must be same and their kinetic energies must be in a ratio of 2000:1 same ratio as that of mass.

Why logical and mathematical aspects are different?What mistake I am doing?
 
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Hi Dex,

Could you leave the template in place ? (or was this thread moved form another subforum?)
What equations do you have to deal with this exercise ?
There is no case of absorbing energy here: the question is purely about the Broglie wavelength
 
This thread is closed. Please use the template provided.
 
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