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2 hours later…
4:47 AM
Q: If you were invisible, would you also be cold? (Since light passes through you, so should thermal radiation)

AlonSee 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...

15 hours later…
7:55 PM
Q: How does the speed of light being measured by the observer who is in motion?

pro100tomI 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...

8:45 PM
Q: Why does the speed of the escape velocity approch to 0?

주성우I 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?


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