Engineering Board Exam Reviewer · Physics · medium
What is the energy of a photon with a wavelength of 500 nm? (h = 6.626 × 10-34 J· s, c = 3 × 108 m/s)
- 1.104 × 10-48 J
- 3.976 × 10-19 J
- 9.939 × 10-32 J
- 3.976 × 10-16 J
Answer
B. 3.976 × 10-19 J
Solution
E = hc/ = (6.626 × 10-34)(3 × 108)/(500 × 10-9) = 3.976 × 10-19 J 2.48 eV.
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