What Is The Speed Of Light?
In Einstein's famous equation E=mc2, did you know that the "c" stands for the speed of light? So what is the actual speed of light? You may be surprised that it's not always a constant.
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TestTube 101 is here to quickly answer all your everyday questions about space, chemistry, physics, biology and more. We've got new videos daily, so keep coming back! Do you have a science question you'd like to get answered? Leave it in the comments below.