An electron can move anywhere along the x axis. The integral of the square of the electron’s wavefunction from x = -∞ to x = ∞ must be equal to

An atom has only two energy levels: E₁ = 3 eV and E₂ = 4 eV. To stimulate the atom to make a transition from the excited state to the ground state, the stimulating photon’s energy must be

100 atoms are initially in an excited state. At time τ (τ, 'tau' is the lifetime of the excited state), how many atoms have made a spontaneous transition to a lower energy state?

Question 5

A hydrogen atom is initially in the 9^th excited state. To escape from the atom, the electron must absorb a photon with what minimum frequency?

Question 4 (cont.)

(b) Calculate the longest wavelength in the range.

Question 4

Consider all possible downward transitions of the electron in a He⁺ ion to the ground state. The emitted photons have a range of wavelength.

(a) Calculate the shortest wavelength in the range.

Question 2

Which material would you choose for the photocathode in a photomultiplier tube that is designed to operate using 1000 nm infrared light?

Question 3 (cont.)

(c) Calculate the kinetic energy (in eV) of the external electron after the collision.

Question 3 (cont.)

The trapped electron is initially in the 5^th excited state. It makes a transition to the 6^th excited state after colliding with an external electron that has a kinetic energy of 8 eV before the collision.

(b) Calculate the voltage required to accelerate the external electron from rest before the collision.

Question 3

An electron is trapped in a 1D box of length L = 1.0 nm.

(a) Calculate the ground state energy (in eV) of the trapped electron.