Why is it that the Earth’s gravity is powerful enough to pull aeroplanes down from the sky if they didn’t move fast enough yet we can easily raise our arms in the air without feeling any force pulling on them?

Question

Why is it that the Earth’s gravity is powerful enough to pull aeroplanes down from the sky if they didn’t move fast enough yet we can easily raise our arms in the air without feeling any force pulling on them?

In: Physics

Answer 1

We *do* feel force on them. It’s just that our muscles are specifically adapted to be big enough to raise our arms. Look how much muscle you have in your shoulders and upper arms, just to move your arms 1 meter upward.