1 / 8

Chapter 7 Linear Momentum

Chapter 7 Linear Momentum. 7.1 Momentum. Linear Momentum- product of mass times velocity p=mv p=momentum units=kg.m/sec Restate Newton’s second law - The rate of change of momentum of a body is equal to the net force applied to it  F=  p/  t pg. 182 Ex. 7-1. 7.2 Conservation of Momentum.

manon
Download Presentation

Chapter 7 Linear Momentum

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapter 7 Linear Momentum

  2. 7.1 Momentum • Linear Momentum- product of mass times velocity • p=mv p=momentum units=kg.m/sec • Restate Newton’s second law - The rate of change of momentum of a body is equal to the net force applied to it • F=p/t • pg. 182 Ex. 7-1 Chapter 7

  3. 7.2 Conservation of Momentum • Law of Conservation of Momentum - The total momentum of an isolated system of bodies remains constant. • Isolated system - one in which the only forces present are those between the objects of the system. • Momentum before = momentum after Chapter 7

  4. Conservation of Momentum • m1vi1 + m2vi2 = m1vf1 + m2vf2 • rocket propulsion - initial momentum = 0 • final total momentum = pgas + procket =0 (same magnitude opposite directions) • pg. 184 Ex. 7-3, 7-4 Chapter 7

  5. 7.4 Conservation of Momentum in collisions • elastic collision - total kinetic energy is conserved • total initial KE = total final KE • 1/2 m1vi12 + 1/2m2vi22= 1/2 m1vf12 + 1/2 m2vf22 • inelastic collision - kinetic energy is not conserved, often changed to thermal energy Chapter 7

  6. 7.5 Solving Problems • Conservation of momentum • Momentum before = momentum after • m1vi1 + m2vi2 = m1vf1 + m2vf2 • Conservation of kinetic energy (elastic collision) • Total KE initial = total KE final • 1/2 m1vi12 + 1/2 m2vi22= 1/2 m1vf12 + 1/2 m2vf22 • V1-V2 = V2’-V1’ = -(V1’ -V2’) Chapter 7

  7. Write two equations • Cancel zero terms • Plug in known variables • Solve for unknown variable Chapter 7

  8. vi1 - vi2 = vf2 - vf1= - (vf1 - vf2) • For any head-on elastic collision, the relative speed of the two particles after the collision has the same magnitude as before, but opposite direction. • pg. 189 Ex. 7-6 & 7-7 Chapter 7

More Related