A ruby laser delivers a 2.28-J pulse in approximately 50 ...

[olgavictoria]

A ruby laser delivers a 2.28-J pulse in approximately 50 nanoseconds. The wavelength of the light is 694.4 nm. At least how many atoms within the ruby rod had to be excited to allow this high-energy laser pulse? (h = 6.63  10-34 Js, c = 3.00  108 m/s, 1 eV = 1.6  10-19 J, and 1 nm = 10-9 m)
 a. 3  1019
  c. 8  1018
  b. 4  1018
  d. 6  1020

Question 2

The wavelength of a coherent laser is 628 nm. What energy difference exists between the upper excited state involved and the lower unexcited ground state? (h = 6.63  10-34 Js, c = 3.00  108 m/s, 1 eV = 1.60  10-19 J, and 1 nm = 10-9 m)
 a. 1.86 eV
  c. 1.75 eV
  b. 1.81 eV
  d. 1.98 eV

[Koolkid240]

Answer to Question 1

C

Answer to Question 2

D

[olgavictoria]

Thanks for the timely response, appreciate it

[essyface1]

Wow, this really help