AP Physics C: Mechanics

Advanced Placement Physics C: Mechanics with calculus-based physics principles.

Advanced Topics

Systems of Particles and Linear Momentum

Beyond Single Objects

Many real-world problems involve multiple interacting objects. The concept of momentum helps us analyze these complex systems.

Linear Momentum

Momentum (\( \vec{p} \)) is mass times velocity: \( \vec{p} = m\vec{v} \). It's a vector, so direction matters!

Conservation of Momentum

In the absence of external forces, the total momentum of a system is conserved: \[ \sum \vec{p}{\text{initial}} = \sum \vec{p}{\text{final}} \]

Center of Mass

Calculus lets us find the center of mass and analyze how a group of particles moves collectively.

Collisions

Elastic and inelastic collisions illustrate momentum conservation and energy transfer.

Real-World Examples

Car crashes and rocket launches rely on these principles to predict outcomes and ensure safety.

Key Formula

\[\vec{p} = m\vec{v}\]

Examples

  • Billiard balls colliding on a pool table demonstrate conservation of momentum.

  • A two-stage rocket uses momentum to separate and propel itself further.

In a Nutshell

Momentum and center of mass principles help us solve problems involving many interacting objects.

Key Terms

Impulse
Change in momentum caused by a force acting over time.
Center of Mass
The average position of mass in a system.