Momentum is a conserved property of a system. This conservation can be demonstrated by using Newton’s third law (Fa/b = -Fb/a) to develop the equation:
mΔva + mΔvb = 0
Momentum is given the lowercase p as its symbol.
The change in momentum (Δp) of an object is defined as impulse.
Impulse = Δp = mΔv = FΔt
Keep in mind that while momentum depends on the same variables as kinetic energy (mass and velocity), momentum and kinetic energy are not the same thing. Momentum is always conserved, but, while energy is conserved, it can move from kinetic storage storage to gravitational, elastic, thermal, etc.
Today’s work
- Today’s handout: Worksheet 1: Momentum and Impulse
- Book: Chapter 6, pages 160-166
- Homework: Page 181, #1-4