Momentum

High School

Definition

The product of an object's mass and velocity, a vector quantity that describes its quantity of motion. A heavy or fast-moving object has large momentum and requires a large force to stop.

Worked examples

\(p = mv = (1200\,\)kg\()(25\,\)m/s\() = 30\,000\,\)kg\(\cdot\)m/s\(\)

A car's momentum equals its mass times velocity; the direction matches the car's direction of travel.

A bowling ball (7 kg, 5 m/s) has more momentum than a tennis ball (0.06 kg, 50 m/s).

Even though the tennis ball moves faster, the bowling ball's greater mass gives it larger momentum.

Common mistakes

momentum is the same as velocity → momentum = mass × velocity Momentum depends on both how massive and how fast an object is; velocity alone is not momentum.
treating momentum as a scalar (ignoring direction) → momentum is a vector pointing in the direction of velocity Momentum has magnitude and direction; opposite velocities give opposite momenta.
\(p = \frac{m}{v}\) → \(p = mv\) Momentum is mass times velocity, not divided by velocity.

Where you'll use it next

You'll use momentum when studying collisions and explosions in physics, analyzing conservation of momentum, understanding impulse and force over time, and solving real-world problems in engineering and sports science.

Found in 1 StudyPug lesson

Momentum and Motion: Essential Concepts in Physics

AS-Level Maths

Dive into the world of momentum and motion. Understand fundamental principles, explore real-world applications, and master problem-solving skills to excel in physics and beyond.

11th Grade11th