See topic. Additionally, I'd like to know if you were wearing invisible clothes, would they keep you warm? In my understanding, the heat radiation from the body would pass through the cloth. Is it even necessary to be permeable for heat radiation in order to be invisible? Could there be a form of...

I am trying to understand the idea that the speed of light is constant for each observer regardless of their motion. But I don't understand how come? I also don't understand how this was measured. Let's say there is a distance from point A to point B and the way to measure it would be to use a st...

I am a little confused about escape velocity. Does the escape velocity always approach 0 as we go infinitely far distance even if there is no friction? If so why does it approach 0? Shouldn't it be moving with constant speed?