Question

An electron is in the ground state of an infinite square well. The energy of the ground state is E₁ = 1.35 eV.

(a) What wavelength of electromagnetic radiation would be needed to excite the electron to the n = 4 state?
nm

(b) What is the width of the square well?
nm

Answer 1

(a).We know the energy of infinite square well is.

..................................(1)

for n=1,   

so equation (1) can also be written like this.

so for n=4.

Now energy difference between n=1 and n=4

(b).width of the box is related to energy correspond to n=1 as

.