Calculate the Frequency of Light from a Helium-Neon Laser

What is the frequency of the monochromatic light from a Helium-Neon laser with a wavelength of 633 nm?

Calculate the frequency of this light in units of THz (1 Terahertz = 10¹² Hz).

Frequency Calculation:

The frequency of light from a Helium-Neon laser with a wavelength of 633 nm is approximately 474 THz.

The frequency of light refers to the number of oscillations or cycles of the electromagnetic wave that pass a given point in one second. It is typically measured in Hertz (Hz), where 1 Hertz is equivalent to one cycle per second.

To calculate the frequency of this monochromatic light, we need to use the formula which combines the speed of light (c) equation c = λv (where λ is wavelength and v is frequency) along with an equation from the Planck-Einstein relation which is E = hv (where h is Planck's constant, v is frequency and E is energy).

Given the data, we will utilize the speed of light equation. Start by converting the 633 nm wavelength to meters because the speed of light is in m/s. So, 633 nm = 633 × 10^-9 m.

The speed of light (c) is 3.00 × 10^8 m/s. Substitute these values into the equation c = λv: 3.00 × 10^8 m/s = (633 × 10^-9 m) × v.

Solving for v, the frequency, we get v ≈ 4.74 × 10^14 Hz. To convert this into terahertz (THz), remember that 1 THz = 10^12 Hz. Therefore, the frequency of this light is approximately 474 THz.