Momentum Introduction

Momentum is the product of an object’s mass and the object’s velocity.


All matter has mass, so if an object is moving, it has momentum!

​

Momentum
Mass in Motion

Momentum is the product of an object’s mass and the object’s velocity thus momentum depends on two variables:

1. Mass

2. Velocity

p (momentum) = ?
m (mass) = 65 kg
v (velocity) = 3 m/s, west

Define Variables

Finding velocity

Finding mass

p (momentum) = 20,000 kg*m/s
m (mass) = 1,500 kg
v (velocity) = ?

Define Variables

Momentum
Vector or Scalar?

Momentum is a vector because it has velocity, which is also a vector.

RECALL: Vectors are quantities that have magnitude (size) and direction, and they are often represented by arrows.

Momentum is always defined relative to a frame of reference. For example, imagine a person driving a car while another person is standing by the side of the road watching the car:

• From the perspective of a stationary observer (the person on the side of the road), the car has momentum because it is moving.

• However, from the perspective of the driver, the car has zero momentum because, in the driver's frame of reference, the car is at rest (zero velocity).

Tip: To make problem-solving easier, always assume the frame of reference is stationary unless otherwise stated!

Reference Frames

Attempt the problems until you can score an 80% or better.