What is the correct formula for calculating the speed of light?

The correct answer is derived from the fundamental relationship between the speed of light, wavelength, and frequency. The speed of light in a vacuum is a constant value, approximately (299,792,458 , \text{m/s}). This relationship can be expressed using the formula:

[ \text{Speed of Light} (c) = \text{Wavelength} (\lambda) \times \text{Frequency} (f) ]

In this formula, wavelength is typically measured in meters, and frequency is measured in hertz (cycles per second). By multiplying these two factors, you arrive at the speed of light.

This highlights that for any electromagnetic wave, including light, its speed can be determined by multiplying its wavelength by its frequency. This is a foundational principle in physics that helps to understand various wave behaviors, including those of radar and lidar systems used in speed detection. Understanding this relationship is crucial, as it underpins how radar and lidar devices function and how they measure speeds based on the emitted and received signals that reflect back from moving objects.