A particle of mass m is trapped between two perfectly rigid parallel walls. The particle bounces back and forth between the walls without losing any energy. From a wave point of view, the particle trapped between the walls is like a standing wave in a stretched string between the walls. Distance between the two walls is L.
(a) Calculate the energy difference between third energy state and the ground state (lowest energy state) of the particle.
(b) Calculate the ground state energy if the mass of the particle is `m = 1 mg` and separation between the walls is `L = 1 cm`.

Answer

(a) `(h^(2))/(mL^(2))` , (b) `5 xx 10^(-54) J`