Calculate the energy in joule corresponding to light of wavelength 45 nm. (Planck's constant, h = 6.63 10-34 J s, speed of light, c = 3 108 m s-1)
- 6.67 1015
- 6.67 1011
- 4.42 10-15
- 4.42 10-18
Answer
(4) 4.42 10-18
Solution
E = hc
= 6.63 10-34 3 10845 10-9
= 19.89 10-264.5 10-8
= 4.42 10-18 J
Answer: (4)