The laser pointer emits light because electrons in the material are excited (by a battery) from their ground state to an upper excited state. When the electrons return to the ground state, they lose the excess energy in the form of 520-nm photons. What is the energy gap between the ground state and excited state in the laser material

Explanation:

the energy gap between the ground state and excited state in the laser material will be equal to energy of photons emitted

Wave length of photons = 520 nm

Energy = 1244 / 520 e V ( Formula for conversion of wavelength in nm to energy in eV )

=   2.4  e V

 the energy gap between the ground state and excited state in the laser material  =   2.4  e V

1= 26.17

2= 1.17

3=30.86

4=5.86

just took the assigment on edge

waves moving from a fast medium to a slow medium will experience a reflection as light travels more slowly than red light. total internal reflection occurs when the critical angle is.