Classical Mechanics Answers

A passenger is on a train moving at a constant forward velocity. The passenger jumps in an upward trajectory. Does the passenger land in the same spot from which he jumped? Or does the passenger lose forward momentum, not being self-propelled, and land behind the spot from which he jumped? What if the train travels at 1000 mph and the passenger jumps 10 miles high? How far (if at all) from the spot that he jumped from will he land?

is it necessary that a force should produce acceleration in a body? if "NO"then what about Newton's 2nd law of motion.

What would happen if the value of G (gravitational constant) was twice as large?

When a balloon sticks to a wall due electrostatic forces between it and the wall why does not it fall down due to weight
As the two electrostatic forces are equal and opposite and net force on balloon is towards wall then how balloon is held on wall

Restoring force of spring is not a reaction force!

If a surface can provide a friction of 5N and we apply a force of 10N then it starts moving but how friction can stip its motion when applied force is more than the friction force

Holding a bottle in air by hand indicates that net force on bottle is 0
But we are applying a force to keep it in air then it is not moving

When we push a block then it moves in a particular direction
But we are also moving in that direction when block is too exerting an equal and opposite force

Why dont two bodies come close when there is a gravitational force between them?
And in an atom two electrons of same or different orbital repel each atom why dont they go away

How to know the displacement produced by a force
By F=ma where a=v/t and where v = d/t