# Doubts in momentum

A body with mass 'm' moves with velocity 'v' possess momentum and the magnitude of momentum of the particle is given by product of its mass and its velocity
Who came up with this idea? On what observation leads to think him like this?
I know that Newton's 2nd law states that force is nothing but rate of change of momentum. So this idea (i.e, concept of momentum) dates back before Newton proposed his laws right, or am i wrong?

ehild
Homework Helper
A body with mass 'm' moves with velocity 'v' possess momentum and the magnitude of momentum of the particle is given by product of its mass and its velocity
It is the definition of momentum.
Newton called it quantity of motion
http://en.wikisource.org/wiki/The_M...of_Natural_Philosophy_(1729)/Definitions#Def1
Definition II.
The Quantity of Motion is the measure of the same, arising from the velocity and quantity of matter conjuctly.
The motion of the whole is the Sum of the motions of all the parts; and therefore in a body double in quantity, with equal velocity, the motion is double; with twice the velocity, it is quadruple.

Who came up with this idea? On what observation leads to think him like this?
I know that Newton's 2nd law states that force is nothing but rate of change of momentum. So this idea (i.e, concept of momentum) dates back before Newton proposed his laws right, or am i wrong?

He formulated his second law as

The alteration of motion is ever proportional to the motive force impressed; and is made in the direction of the straight line in which that force is impressed.
If any force generates a motion, a double force will generate double the motion, a triple force triple the motion, whether that force be impressed altogether and at once, or gradually and successively. And this motion (being always directed the same way with the generating force), if the body moved before, is added to or subtracted from the former motion, according as they directly conspire with or are directly contrary to each other; or obliquely joined, when they are oblique, so as to produce a new motion compounded from the determination of both.

http://en.wikisource.org/wiki/The_Mathematical_Principles_of_Natural_Philosophy_(1729 [Broken])

His Principles was based on the experimental observations of Galilei and others.

ehild

Last edited by a moderator:
• 1 person