Question

calculate the frequency in hertz of electromagnetic radiation that has a wavelength of 720.0 nm. (c = 3.00 × 10^8 m/s)

Explanation:

Step1: Convert wavelength to meters

$720.0\ nm = 720.0\times10^{-9}\ m$

Step2: Use the formula $c = \lambda

u$
We know $c = 3.00\times 10^{8}\ m/s$ and $\lambda=720.0\times 10^{-9}\ m$. Rearranging for $
u$ gives $
u=\frac{c}{\lambda}$.
$
u=\frac{3.00\times 10^{8}\ m/s}{720.0\times 10^{-9}\ m}$

Step3: Calculate the frequency

$
u=\frac{3.00\times 10^{8}}{720.0\times 10^{-9}}\ Hz\approx4.17\times 10^{14}\ Hz$

Answer:

$4.17\times 10^{14}\ Hz$