4 Answered Questions for the topic newtonian gravity
Does the mass of a star change as it collapses into a black hole?
I know (I think!) that when a really big star collapses on itself it creates a black hole. My question: When a star collapses, is the mass equal to the mass of the star when it's not a black hole?... more
How can I stand on the ground? EM or/and Pauli?
There is this famous example about the order difference between gravitational force and EM force. All the gravitational force of Earth is just countered by the electromagnetic force between the... more
Does juggling balls reduce the total weight of the juggler and balls?
A friend offered me a brain teaser to which the solution involves a $195$ pound man juggling two $3$-pound balls to traverse a bridge having a maximum capacity of only $200$ pounds. He explained... more
Why is the Moon considered the major cause of tides, even though it is weaker than the Sun?
You have likely read in books that tides are mainly caused by the Moon. When the Moon is high in the sky, it *pulls* the water on the Earth upward and a high-tide happens. There is some similar... more