The eye perceives light in the range of approximately 380 to 760 nm. How many times are the frequencies

The eye perceives light in the range of approximately 380 to 760 nm. How many times are the frequencies corresponding to the boundaries of the visible spectrum different?

The extreme wavelengths of the range are set:

λ1 = 38 * 10-8 m;

λ2 = 76 * 10-8 m.

We find the corresponding frequencies:

v1 = c / λ1;

v2 = c / λ2.

We find the relation:

v1 / v2 = (c / λ1) / (c / λ2) = λ2 / λ1 = (76 * 10-8 m) / (38 * 10-8 m) = 2.

The upper frequency of electromagnetic waves perceived by the human eye as light is twice the lower frequency.

Answer. 2 times.