Question

A. What is the frequency of blue light that has a wavelength of 450 nm?

Answer 1

Answer

a)Given,

Wavelength of blue light = 450 n m = 450 x 10⁻⁹ m

 Speed of light = 3 x 10⁸ m/s

we know,

       $c = \nu \lambda$

       $\nu = \dfrac{c}{\lambda}$

       $\nu = \dfrac{3\times 10^8}{450\times 10^{-9}}$

      $\nu = 6.67 \times 10^{14}\ Hz$

b)Given,

Wavelength of red light = 650 n m = 650 x 10⁻⁹ m

 Speed of light = 3 x 10⁸ m/s

we know,

       $c = \nu \lambda$

       $\nu = \dfrac{c}{\lambda}$

       $\nu = \dfrac{3\times 10^8}{650\times 10^{-9}}$

      $\nu = 4.62 \times 10^{14}\ Hz$