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

increases it

when jerome paddle in flowing river towards east the net speed of jerome will increase

so the net speed of jerome will be given as

now the speed of paul will be same as it is given as he is running on the ground

so

so here we can say since the speed of jerome is more so he will win the race

now as we know the distance so the time difference is given as

so jerome will reach first and the time difference will be 203.55 s or 3.4 min