Question

The wavelength of visible light is:
A. 200nm-370nm
B. 780nm-890nm
C. 380nm-760nm
D. 900nm-2000nm

Answer 1

Hint- As we know, Wavelength of light is designated as the distance between the two successive crests of the light wave. Therefore, we simply say the distance between either one crest or trough of one wave and the next wave is called wavelength. And It is denoted by the letter lambda (λ).

Complete step-by-step answer:
Mathematically, wavelength of light calculated:
As light has the properties of a wave as well as particle, it can be expressed as:
$c = \lambda f$
Where, c- speed of light
$\lambda$- wavelength of the light.
$f$- the frequency of the light.
The wavelength for various colours of the visible range of spectrum of light is provided in the below table underneath.

Typically, it’s 400nm to 700nm (Violet to Red) but we have some sensitivity to UV below 400nm (about 10 to 20nm I think) and some sensitivity to IR above 700nm - up to around 1350nm. After that, we might still have sensitivity, but the resultant energy from the light would damage our eyes rather than be simply detected.

Therefore, roughly it is from 400nm to 750 nm. The lens in your eye absorbs below 400 nm. In days before the use of lens inserts, people could see down to 350 nm after cataract surgery (removal of the natural lens). The long wave limit is not sharp and you might see something out near 800nm.

Note- Remember always, We can see that visible spectrum have wavelength range of 400nm to 700nm but in Angstrom we can also say 4000 ${{\text{A}}^{\text{0}}}$to 7000 ${{\text{A}}^{\text{0}}}$. And where 1 ${{\text{A}}^{\text{0}}}$ is equal to 0.1 nanometers.