A particle in one dimension is in an infinite potential well between -L/2 ≤ x ≤ L/2. For a perturbation ε cos(πx/L), where ε is a small constant, the change in the energy of the ground state to first order in ε is:

In quantum mechanics, the eigenvalue of a Hamiltonian operator for a particle is used to determine which of the following physical quantities?

Which of the following is a mandatory mathematical characteristic of an acceptable wave function in quantum mechanics?