The time it takes for light to travel from point A to point B in a vacuum can be calculated using the equation:
Time = Distance / Speed
In this case, since light travels at a constant speed in a vacuum, the speed of light is approximately 299,792 kilometers per second (or about 186,282 miles per second).
So, if you know the distance between point A and point B, you can divide that distance by the speed of light to find the time it takes for light to travel that distance in a vacuum. For example, if the distance between point A and point B is 300,000 kilometers, the calculation would be:
Time = 300,000 kilometers / 299,792 kilometers per second ≈ 1.000001 seconds
Therefore, it would take approximately 1.000001 seconds for light to travel a distance of 300,000 kilometers in a vacuum.