The wavelength of ultraviolet radiation is 400nm. If the speed of light in air is 3 x 10\(^8\)ms\(^{-1}\), then the frequency of the ultraviolet radiation is
A
1.3 x 1015Hz
B
7.5 x 105Hz
C
1.2 x 1011Hz
D
7.5 x 1014Hz
Verified Correct Answer: D.
Physical Principles & Numerical Solution
F = \(\frac{V}{\lambda}\)
= \(\frac{3 \times 10^8}{400 \times 10^{-9}}\)
= 0.75 x 10\(^{15}\)Hz
= 7.5 x 10\(^{14}\) Hz
Source: Myschool Past Questions Archive (Record #28546)