Momentum is a commonly used term in sports. When a sports announcer says that a team has the momentum they mean that the team is really on the move and is going to be hard to stop. The term momentum is a physics concept. Any object with momentum is going to be hard to stop. To stop such an object, it is necessary to apply a force against its motion for a given period of time. The more momentum that an object has, the harder it is to stop. Thus, it would require a greater amount of force or a longer amount of time or both to bring such an object to a halt. As the force acts upon the object for a given amount of time, the object’s velocity is changed; and hence, the object’s momentum is changed.

Key terms

• Momentum: the product of mass and velocity of a body. It is a vector quantity which takes the direction of velocity. It describes the effort required to set a body in motion or to stop it.
• Impulse: The product of the force applied and the time for which the force is acting. It is equal to the change of momentum.