First Law Of Newton
Everybody will persist in its state of rest or of uniform motion (constant velocity) in a straight line unless and untill it is compelled to change that state by forces impressed on it. This means that in the absence of a non-zero net force, the center of mass of a body either is at rest or moves at a constant velocity.
EXAMPLE
If we drop a marble from a height h, then the marble will roll and try to get to h and if he is not able to, then it keeps on moving.
page revision: 5, last edited: 23 Aug 2010 09:49