Question

Calculate the frequency of yellow light of wavelength $550nm$. The speed of light is $3\times {10}^{8}m{s}^{-1}$

• A. $5.4\times {10}^{11}Hz$
• B. $5.4\times {10}^{14}Hz$
• C. $2.7\times {10}^{14}Hz$
• D. $2.7\times {10}^{11}Hz$

Answer 1

Answer: (B)

Given,

Wavelength of yellow light = $\lambda =550nm=550\times {10}^{-9}m$

Velocity of light = $v=3\times {10}^{8}m{s}^{-1}$.

We know that, the frequency of the wave is given by

$f=\frac{v}{\lambda }$

where $v$ is the velocity of wave and $\lambda$ is the wavelength of the wave.

$\therefore f=\frac{3\times {10}^{8}m{s}^{-1}}{550\times {10}^{-9}m}=5.4\times {10}^{14}Hz$

Thus, the frequency of yellow light is $5.4\times {10}^{14}Hz$.

Hence option (b) is correct.