Linear momentum
From Mech
Contents
Definition
For a single body in pure translation
The linear momentum of a body is the vector , where
is the mass of the body and
is the velocity of the body.
For a system of bodies, each in pure translation
The linear momentum of a system is the sum of the linear momenta of all the bodies in that system. If the system comprises bodies with masses
respectively and velocities
respectively, the total linear momentum is given by:
This is a vector summation.
For a single body undergoing motion that is not purely translation
In this case, we integrate the velocity vector over a mass differential:
This is equivalent to integrating the product of velocity and density over a volume differential:
Units and dimensions
Question | Answer |
---|---|
Scalar or vector? | Vector |
Instantaneous or time-cumulative | Instantaneous |
MLT dimensions | ![]() |
SI units | ![]() ![]() |