Question

The bright line spectrum of Neon contains a line with the wavelength of 700 nm. What is the

frequency of this light and what color is it?

Answer 1

1) The frequency of the light is approximately 4.283 × 10¹⁴ Hz

2) The color of the light is red

Explanation:

1) The given parameter;

The wavelength of the line contained in the Neon spectrum, λ = 700 nm = 0.0000007 m = 7.0 × 10⁻⁷ m

The speed of light, v = 299,792,000 m/s

v = f × λ

The frequency, f of the light = v/λ = 299,792,000/(7.0 × 10⁻⁷) ≈ 4.283 × 10¹⁴ Hz

The frequency of the light ≈ 4.283 × 10¹⁴ Hz

2) Given that light with wavelength between 620 - 750 nm constitute red light, we have that the given light with a wavelength of 700 nm is a red light source.