Impulse and momentum

Science

Definition

Momentum is the product of an object's mass and velocity (p = mv), representing how hard it is to stop a moving object. The impulse-momentum theorem states that the impulse applied to an object equals its change in momentum (FΔt = Δp).

Examples

  • A heavy truck at low speed having the same momentum as a light car at high speed
  • Catching an egg by moving your hand back to increase contact time and reduce force
  • Rockets expelling gas backward to gain forward momentum
Key Fact

p = mv; FΔt = mΔv = Δp

Related Terms

Impulse Conservation of momentum Collisions Newton's three laws

Study This Concept

Practice impulse and momentum with free review games in these units:

Physics Unit 4: Momentum and Collisions