Does gravitv & air resistance affect speed of light?
Oddly enough, light travels more quickly through a vacuum than it does through Earth’s atmosphere. It’s not really due to ‘air resistance,’ but unless you want to go into and beyond the quantum mechanics of it all, let’s just say that, yes, it does effect the speed of light. You get the same effect with glass and water – refractions are due to light changing speed as it enters a new substance in which it travels either more quickly or slowly than the medium it just left. Gravity, well, that goes without saying. Just look at a black hole – the gravity of such features can be so great as to not only change the velocity of light, but alter its path to such a degree that it gets sucked in. A change in direction can also be seen as an acceleration in a direction other than the initial – in other words, the light is accelerated towards the black hole. This is how we can detect black holes – light from stars directly behind them is sucked in, but light that would have passed close enough to t
