laser pointer green 532 nm photon energy

laser pointer green 532 nm photon energy

 

 

a) A green laser pointer emits light with a wavelength of 532 nm.

What is the frequency of this light?

b) What is the energy of one of these photons?

c) 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 532 nm photons.

What is the energy gap between the ground state

and excited state in the laser material?

 

---------------------------------------------------

 

a)

ν = c / λ

( 참고 https://ywpop.tistory.com/4964 )

 

= (2.998×10^8 m/s) / [532 nm × (1 m / 10^9 nm)]

= (2.998×10^8) / [532 × (1 / 10^9)]

= 5.6353×10^14 /s

= 5.64×10^14 /s

= 5.64×10^14 Hz

 

 

 

b)

E = hν

= (6.626×10^(-34) J•s) (5.64×10^14 /s)

= (6.626×10^(-34)) (5.64×10^14)

= 3.74×10^(-19) J

 

(6.626×10^(-34)) (5.6353×10^14) = 3.73×10^(-19) J

 

 

 

c)

ΔE = hν

= (6.626×10^(-34) J•s) (5.64×10^14 /s)

= (6.626×10^(-34)) (5.64×10^14)

= 3.74×10^(-19) J

 

The energy gap between the ground and excited states

is the energy of a single 532 nm photon emitted

when one electron relaxes from the excited to the ground state.

ΔE = 3.74×10^(-19) J

 

전자 1개가 바닥상태 → 들뜬상태 전이할 때 흡수한 에너지

= 전자 1개가 들뜬상태 → 바닥상태 전이할 때 방출한 에너지

= 광자(= 빛) 1개의 에너지

( 전자가 흡수한 에너지를 방출할 때는 빛의 형태로 방출. )

= 바닥상태의 에너지 준위와 들뜬상태의 에너지 준위 차이

= 바닥상태의 에너지와 들뜬상태의 에너지의 간격