A0.100-ma electron beam with kinetic energy 54.0 ev enters a sharply defined region of lower potential where the kinetic energy of the electrons is increased by 10.0 ev. what current is reflected at the boundary? (this simulates electron scattering at normal incidence from a metal surface, as in the davisson–germer experiment.)

Explanation:

The reflection coefficient is the ratio of reflected flux to the incident flux

The reflection coefficient of a srep potential when a particle is is incident on the barrier is given as:

Where is the propagation constant of the incident  wave and is the propagation constant of transmitted wave.

The expression for the is given as:

Here is the electron mass; the reduced plancks constant; the speed of light and the energy of the incident wave.

substituting for ; for and for in the equation

this is the propagation constant for the incident wave.

For

Here is the electron mass; the reduced plancks constant; the speed of light and the energy of the incident wave.

substituting for ; for and for in the equation

this is the propagation constant for the transmitted wave.

substituting for and  

The ratio of the reflected current to the incident current is the reflection coefficient.

substituting 0.0018 for R and 0.100mA for

learn it on the intertant so you can solve

i think the answer would be reserve.