Transcript:

So, here's the thing about fog. It seems like when we walk towards the fog, it starts thinning out. Right, so look, I'm walking towards it, and suddenly, I can feel that the fog is thinning out. That's not what is happening.

So here's what's happening in the fog. The object that we see is because the light that is reflected off that object is reaching our eye. And when we are away from the object, the fog, the water molecules in the fog, scatter that light away, and that object cannot be seen clearly. As we move closer to the object, the scattering reduces, and then the visibility improves.

This is the importance of driving in fog. You have to drive slow because the visual depth of vision keeps progressively increasing as you move, but it increases at the same speed at which you're moving. So you have to drive really slow in fog.