question_answer 26)

Calculate the wavelength, frequency and wave number of a light whose period is \[2\times {{10}^{-10}}\sec .\]

Answer:

Frequency \[(v)=\frac{1}{\text{Time}\,\text{period}\,(T)}\] \[=\frac{1}{2\times {{10}^{-10}}}{{\sec }^{-1}}=5\times {{10}^{9}}Hz\] \[v=\frac{c}{\lambda }\] \[\lambda =\frac{c}{v}=\frac{3\times {{10}^{8}}}{5\times {{10}^{9}}}\] \[=0.06m\]