Answer:
from 7.69×10¹⁵ Hz
Step-by-step explanation:
Frequency: This can be defined as the number of complete cycle a wave complete in one seconds, the S.I unit of frequency is Hertz (Hz).
From the question,
v = λf............. Equation 1
Where v = speed of visible light in air, λ = wave length of visible light, f = frequency of visible light.
make f the subject of the equation
f = v/λ.................... Equation 2
Note: all electromagnetic wave have the same speed = 3×10⁸ m/s
Given: v = 3×10⁸ m/s, λ = from 3.9×10⁻⁷ m
Substitute into equation 2
f = 3×10⁸/ 3.9×10⁻⁷
f = 7.69×10¹⁵ Hz
Hence the range of the frequencies for visible light = from 7.69×10¹⁵ Hz