Red lights on a traffic light have a frequency of 4.3 X 1015 Hz. What is the red light’s wavelength in meters?

The wavelength of light is found to be 6.98  × 10^-8 m.

We know that light is an electromagnetic wave, the speed of an electromagnetic wave is commonly referred to as the speed of light which has a numerical value of 3 × 10^8 m/s.

Now;

c = λf

c = speed of light

λ = wavelength of light

f = frequency of light

But;

λ = c/f

λ =  3 × 10^8 m/s/ 4.3 X 10^15 Hz

λ = 6.98  × 10^-8 m

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