(adsbygoogle = window.adsbygoogle || []).push({}); An atom of mass [tex]M[/tex] is initially at rest, in its ground state. A moving (nonrelativistic) electron of mass [tex]m_e[/tex] collides with the atom. The atom+electron system can exist in an excited state in which the electron is absorbed into the atom. The excited state has an extra, "internal," energy, E, relative to the atom's ground state.

Find the kinetic energy[tex] K_e[/tex] that the electron must have in order to excite the atom.

Express your answer in terms of E, M , and [tex]m_e[/tex] .

Ok, I've gotten this part so far: [tex] K_e = E + 1/2 * (M+m_e)v_2^2[/tex]

But how do you get rid of [tex]v_2^2[/tex]? The computer says that my answer shouldn't depend on [tex]v_2[/tex].

How do I get rid of v...or Is my equation wrong?

Thanks

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# Homework Help: Kinetic Energy and Nonrelativistic Collision

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