Atomic Structure Question 126
Question: The frequency of a wave of light is $ 12\times 10^{14}{s^{-1}}. $ The wave number associated with this light is [Pb. PMT 1999]
Options:
A) $ 5\times {10^{-7}}m $
B) $ 4\times {10^{-8}}c{m^{-1}} $
C) $ 2\times {10^{-7}}{m^{-1}} $
D) $ 4\times 10^{4}c{m^{-1}} $
Show Answer
Answer:
Correct Answer: D
Solution:
Frequency $ \nu =12\times 10^{14}{s^{-1}} $ and velocity of light $ c=3\times 10^{10}cm,{s^{-1}} $ . We know that the wave number $ \overline{\nu }=\frac{v}{c}=\frac{12\times 10^{14}}{3\times 10^{10}}=4\times 10^{4}c{m^{-1}} $