http://www.ck12.org Chapter 4. Motion and Forces
4.27 Momentum
- Define momentum.
- Relate momentum to mass and velocity.
- Calculate momentum from mass and velocity.
Cody seems a little reluctant to launch himself down this ramp at Newton’s Skate Park. It will be his first time down
the ramp, and he knows from watching his older brother Jerod that he’ll be moving fast by the time he gets to the
bottom. The faster he goes, the harder it will be to stop. That’s because of momentum.
What Is Momentum?
Momentumis a property of a moving object that makes it hard to stop. The more mass it has or the faster it’s
moving, the greater its momentum. Momentum equals mass times velocity and is represented by the equation:
Momentum = Mass×Velocity
Q: What is Cody’s momentum as he stands at the top of the ramp?
A: Cody has no momentum as he stands there because he isn’t moving. In other words, his velocity is zero. However,
Cody will gain momentum as he starts moving down the ramp and picks up speed.
Q: Cody’s older brother Jerod is pictured in theFigure4.51. If Jerod were to travel down the ramp at the same
velocity as Cody, who would have greater momentum? Who would be harder to stop?