An un-scientific Mind

Things I wonder about:

1. Last week we recreated a science experiment that I saw demonstrated on TV by someone from the Museum of Science and Industry. (See the video below.) We threw a cup of boiling water into the air when it was 9 below zero here, and the water froze mid-air. But when we tried it first with cold water, which intuitively seems to make more sense, since cold water is already, well, colder, it didn't work. Why?

2. The shortest distance between 2 points is a straight line; but if you're flying from, say, Paris to Chicago, you have to follow the curvature of the earth, so does that mean it's not really a straight line? If you really went straight, would you have to bore a tunnel through the earth?

These are the things I wonder about, because in His great wisdom, G-d blessed me with a very curious mind, but unfortunately not the mathematical or scientific talents to understand those things!