Question

What does it mean when momentum is zero?

Answer 1

1. Momentum$\left(p\right)$ of a body is defined as the product of its mass$\left(m\right)$ and velocity$\left(v\right)$.
   Mathematically, $p=mv$.
2. An object is said to have zero momentum when either the mass or the velocity is zero.
3. Since the mass of the object cannot be zero, the velocity of the object must be zero for momentum to be zero.
4. Velocity of an object is zero means the object is at rest.
5. Thus, the momentum of an object is zero means the object is at rest.