+76 If you had a perfectly clear sphere that was perfectly filled, you couldn't tell by looking at it whether it was filled with solid glass, water, air, or a vacuum. amirite?

by Anonymous 2 years ago

Those things all have a different refraction index, meaning they bend light in different ways.

by Anonymous 2 years ago

I know a hoover when I see one!

by Anonymous 2 years ago

Duh! It would still be subject to refraction index!

by Anonymous 2 years ago