Question

There are two categories of ultraviolet light. Ultraviolet A ( UVA ) has a wavelength ranging from 320nm to 400nm . It is not so harmful to the skin and is necessary for the production of vitamin D. UVB, with a wavelength between 280nm and 320nm , is much more dangerous, because it causes skin cancer

PART A

Find the frequency ranges of UVA.

Enter your answers separated with commas.


fmin,fmax= 7.50

Answer 1

7.5 * 10^(14) Hz to 9.375 * 10^(14) Hz.

Step-by-step explanation:

The minimum wavelength, λ₁ = 320 nm = 3.2 * 10⁻⁷ m

The corresponding frequency can be obtained by using the formula of speed of light:

c = λ₁ * f₁

f₁ = c / λ₁

f₁ = ( 3 * 10^8) / (3.2 * 10^(-7))

f₁ = 9.375 * 10^(14) Hz

The maximum wavelength, λ₂ = 400 nm = 4 * 10⁻⁷ m

The corresponding frequency can be obtained by using the formula of speed of light:

c = λ₂ * f₂

f₂ = c / λ₂

f₂ = ( 3 * 10^8) / (4 * 10^(-7))

f₂ = 7.5 * 10^(14) Hz

The frequency range of UVA is therefore 7.5 * 10^(14) Hz to 9.375 * 10^(14) Hz.