Momentum (p) is equal to the product of an object's mass and its velocity, it also represents an object's tendency to stay in motion. The quantity of Impulse (J) changes the value of momentum. Impulse is defined as a force over an amount of time and this can be calculated using a Force vs. Time graph.
Types of Collisions:
Elastic Collision
Elastic Collision
- Hard collision, no deformation
- No loss in momentum or kinetic energy
- Deformation occurs
- No loss in momentum, loss in kinetic energy
- Objects end up with different velocities
- Deformation occurs
- No loss in momentum, loss in kinetic energy
- Becomes one object
- Objects end up with one velocity
- No change in momentum, kinetic energy is gained
- Momentum of center of mass in unchanged
Impulse:
- Impulse is the force exerted over a certain time.
- Represented with the variable "J"
- Impulse also equals the change in momentum (Δp)
- Δp= Fnet * Δt, which means the change in momentum, or the impulse, is equal to the net force times the change over time
- Units to measure impulse are N*s or kg*m/s
- Impulse is the area under a Force vs. Time graph
Momentum:
- Momentum is how hard it is to stop something
- Represented with the variable "p"
- Momentum equals the product of mass and velocity (mv)
- Impulse equals a change in momentum
- Momentum is conserved if there are no external forces acting on the object
- A velocity vector and momentum vector of an object are in the same direction
- Units to measure momentum are N*s or kg*m/s
LIL Charts:
Qualitative representation of conservation of momentum and change in impulse to determine an overall prediction of a situation. The following graphs are from the previous Momentum Lab
Qualitative representation of conservation of momentum and change in impulse to determine an overall prediction of a situation. The following graphs are from the previous Momentum Lab
Conservation of Momentum:
- Isolated system: pinitial (pi) = pfinal (pf)
- Other systems: pi + J (impulse) = pf
- Center of mass is always the same momentum
Relating Momentum, Forces, Energy, and Kinematics