Bohr's model of hydrogen like atoms question.

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vkash
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Homework Statement



A neutron moving with speed v makes head on collision with a hydrogen atom in ground state kept at rest. Find the minimum Kinetic energy of the neutron for which inelastic(completely of partially) collision may take. (mass of neutron=mass of hydrogen=~1.67*10-27)

Homework Equations



Bohr's model of hydrogen atom.

The Attempt at a Solution


I didn't know even how to proceed??
can u please help.
 
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Hi vkash,

How can be the collision between neutron and hydrogen atom inelastic? what happens to the KE of the neutron?

ehild
 
ehild said:
Hi vkash,

How can be the collision between neutron and hydrogen atom inelastic? what happens to the KE of the neutron?

ehild

I think according to question collision is similar as it happen when bullet is fired on a block after firing block and bullet move together. Here it might attack on hydrogen atom to form deuterium??
See attachment for it's solution. I want to understand what happened in the solution??
Little bad quality. But try to manage.
 

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Can you imagine some other reaction during collision than making a deuteron? Think of the electron of the hydrogen atom. By the way, the problem says that the hydrogen atom is kept in rest.

ehild
 
ehild said:
Can you imagine some other reaction during collision than making a deuteron? Think of the electron of the hydrogen atom. By the way, the problem says that the hydrogen atom is kept in rest.

ehild

Doesn't got the point.
Electron can neither attract neutron nor repel so how can i calculate the work.
I think any velocity can do inelastic collision. How velocity can tell us that either collision is elastic or inelastic?
 
The neutron can kick out the electron from its ground level and rise to a next one.

ehild
 
vkash said:
Doesn't got the point.
Electron can neither attract neutron nor repel so how can i calculate the work.
I think any velocity can do inelastic collision. How velocity can tell us that either collision is elastic or inelastic?
Consider why momentum is always conserved but kinetic energy isn't in a collision. With momentum, there's no way to "hide" it inside the object. If an object of mass m has momentum p, it has to move with speed v=p/m. Energy, however, can be hidden inside the object, for example, by heating it up, so energy gained by an object doesn't have to be in the form of kinetic energy. When some of the initial kinetic energy gets turned into this hidden form, you get an inelastic collision.

This is what ehild is trying to get you to figure out. How can the atom "store" energy so that the collision ends up being inelastic?
 
As the title says Bohr Model, the problem has to be connected to the Bohr Model of electron orbitals and energy...

ehild
 
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