How much stronger is the electric force between two protons than the gravitational force between them?

When the force acting on an object points at least partially in the direction of the motion the work done is considered to be negative

Which best represents the law of conservation of mass ?

Apebble is thrown into a calm lake, ripples are formed from the center and move outward. the water particles in the lake travel in a circular pattern that moves up and down on the surface of a lake, and the energy travels a) diagonally. b) downward. c) horizontally. d) upward.