Neutron velocity, energy change time/distance

[hebejere]

this is really basic I know but i would like to know if a neutron ,positron or alpha particle of a given energy will lose energy and velocity as it travels through space would atmospheric molecules have a significant effect as well on velocity/energy level. and if they do lose energy what form is that energy in?

 

[hebejere]

or is it like the conservation of energy wherein something will maintain its energy level only if interacted with. ie with no atoms to strike a neutron will continue on indefinitely at the same energy. yes?

 

[mathman]

or is it like the conservation of energy wherein something will maintain its energy level only if interacted with. ie with no atoms to strike a neutron will continue on indefinitely at the same energy. yes?

Yes

 

[Astronuc]

this is really basic I know but i would like to know if a neutron ,positron or alpha particle of a given energy will lose energy and velocity as it travels through space would atmospheric molecules have a significant effect as well on velocity/energy level. and if they do lose energy what form is that energy in?

Neutrons are neutral particles; they interact through collisions with atomic nuclei. Electrons/positrons and alpha particles are charged, and therefore interact coulombically with atomic electrons and occasionally with nuclei. In those interactions, the neutron or charge particle will lose kinetic energy.

Charged particles can also interact with electric and magnetic fields, which are produced by distributions of charged particles.

 

[Dennis Jasbey]

Neutrons will not travel forever in space.

Free neutrons decay into protons and electrons with a halflife of about 10 minutes.