An electron collides with a free molecules initially in its ground state. The collision leaves the molecules in an excited state that is metastable and does not decay to the ground state by radiation. Let K be the sum of the initial kinetic energies of the electron and the molecule, and `vecP` the sum of their initial momenta. Let K' and `vecP` represent the same physical quantities after the collision. Then

Options

A. `K=K',vecP=vecP'`
B. `K' lt K, vecP=vecP'`
C. `K=K',vecP ne vecP'`
D. `K' lt K, vecP ne vecP'`

Answer

B