Question

What is the frequency of a helium-neon laser light with a wavelength of 632.8 nm? The speed of light is `3.00 * 10^8 "m/s"`.

Answer 1

The frequencyof the laser will be `4.471 * 10^(14)"s"^(-1)`.

This is a basic plug and play problem in which all you have to do is use the values for wavelength and speed of light given to you for this equation

`nu = c/(lamda)`, where

`nu` - frequency;
`c` - the speed of light;
`lamda` - wavelength.

Before calculating the frequency of the laser, convert the wavelength from nm to m

`632.8cancel("nm") * "1 m"/(10^(9)cancel("nm")) = 632.8 * 10^(-9)"m"`

Now you're good to go. The frequency will be equal to

`nu = c/(lamda) = (3.00 * 10^(8)cancel("m")"s"^(-1))/(632.8 * 10^(-9)cancel("m")) = color(green)(4.74 * 10^(14)"s"^(-1))`