A beam of particles of energy E = 9 eV strikes on a step potential and 25% of the beam's particles is reflected back. What is the height of the step potential?
(A) 4 eV
(B) 8 eV
(C) 3 eV
(D) 1 eV
(E) 5 eV
√(R) = [√(E)-√(E-U)]/[√(E)-√(E_U)]
The Attempt at a Solution
Just plug and chug the equation I have, but this is for a timed test without a calculator or equation sheet. This seems clunky to remember, solve and do in such conditions. Is there a simpler way? I get 8eV, which is the correct answer.