**Q7: **

Photons are emitted by an electron that is confined to a box. The longest wavelength of the emitted photons is 500 nm. What is the width of the box?

- A m
- B m
- C m
- D m
- E m

**Q8: **

What is the ground state energy of an alpha-particle confined to a one-dimensional box of length 15.0 fm?

**Q9: **

An electron confined to a box has a ground state energy of 2.5 eV. What is the width of the box?