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Question

Question: Is momentum energy?...

Is momentum energy?

Explanation

Solution

The product of mass and velocity is momentum. It is the property of a moving body under the action of external forces. While energy is the ability of a body to do work, energy is possessed by a body by virtue of its motion or position. Momentum is a vector quantity but energy is a scalar quantity.

Complete answer:
The product of mass and velocity is momentum. It is a vector quantity. Its SI unit is metre per second (ms1m{{s}^{-1}}). Therefore,
p=mvp=mv
Here, pp is the momentum
mm is the mass
vv is the velocity
Momentum is a property of the motion of a body and is not energy. The ability of a body to do work is the energy possessed by it. Energy is possessed by a body due to its motion or position while momentum is only due to the motion of a body. Also, energy is a scalar quantity and its unit is joules (J)
The rate of change of momentum is the force acting on a body,
ΔpΔt=F\dfrac{\Delta p}{\Delta t}=F
Here, Δp\Delta p is the change in momentum
Δt\Delta t is the time interval
FF is the force
The energy and the momentum of a body are related as-
K=12mv2 K=12(mv)v \begin{aligned} & K=\dfrac{1}{2}m{{v}^{2}} \\\ & \Rightarrow K=\dfrac{1}{2}(mv)v \\\ \end{aligned}
Here, KK is the kinetic energy
We know that, p=mvp=mv in the above equation, substituting given values to get,
K=12pvK=\dfrac{1}{2}pv
Therefore, momentum is a property of a body due to its motion and is not energy.

Note:
As the momentum remains constant with time, the force is hence, the momentum is conserved when no force is acting on a body. In rotational motion, the angular momentum is analogous to linear momentum. The direction of momentum is the same as the direction of velocity.