A laser emits light of wavelength 463 nm during a brief pulse that lasts for 25 ms and has a total energy of 1.2 J. How many photons are emitted in that single pulse? (c = 3.00 × 108 m/s, h = 6.626 × 10-34 J • s)
A) 2.8 × 1018
B) 6.9 × 1019
C) 3.4 × 1019
D) 1.1 × 1017
E) 2.2 × 1017
A
Physics & Space Science
You might also like to view...
The energy released when an unstable electron state decays has an uncertainty of about 0.50 eV
What is the uncertainty in the life-time of the level? (h = 6.626 × 10-34 J ? s, 1 eV = 1.60 × 10-19 J) A) 1.3 × 10-11 s B) 1.3 × 10-15 s C) 8.3 × 10-11 s D) 8.3 × 10-15 s
Physics & Space Science
What is the proper abbreviation for ‘grams?'
a. g b. gms c. gm d. gr e. kg
Physics & Space Science
An absorption spectrum is also called a bright line spectrum
Indicate whether the statement is true or false
Physics & Space Science
Two charged particles repel each other with a force F. If the charge of both particles is tripled and the distance between them is also tripled, then the force will be
A) F. B) 2 F. C) F/2. D) F/4. E) none of the above
Physics & Space Science