Question

In a laser, the lasing levels are the first excited state and the ground state of the

active medium. If the energy of the first excited state is 1.5eV, calculate the

frequency of the laser light

Answer 1

$\boxed {\upsilon ={ E_f-E_i \over h}}$

$\upsilon = frequency$ ( in Hz)

$E_f =$ a higher level having energy (in ev)

$E_i =$ ground state or a lower lying excited state energy (in ev)

h = planks constant (in ev s)

$\boxed {\upsilon ={ 1.5ev-13.6ev \over 4.1357 × 10^{-15} ev\space s}}$

$\boxed {|\upsilon | ={2.925 \times 10^{15}Hz }}$