A) \[{{10}^{18}}Hz\]
B) \[{{10}^{14}}Hz\]
C) \[{{10}^{9}}Hz\]
D) \[{{10}^{16}}Hz\]
Correct Answer: B
Solution :
Key Idea: Infrared rays are electromagnet rays having velocity \[3\times {{10}^{8}}\,m/s\] We know that \[\text{Frequency}\,\text{=}\,\frac{\text{velocity}}{\text{wavelength}}\] For infrared rays \[\lambda =10,000\overset{\text{o}}{\mathop{A}}\,={{10}^{4}}\times {{10}^{-10}}\,m={{10}^{-6}}m\] \[\therefore \] \[f=\frac{3\times {{10}^{8}}}{{{10}^{-6}}}=3\times {{10}^{14}}\,Hz\] Hence, frequency of infrared rays is approximately \[{{10}^{14}}\,Hz.\]
You need to login to perform this action.
You will be redirected in
3 sec
