Momentum Ch 6.3 8th

Chapter 6 Section 3

Objectives: 

Calculate the momentum of moving objects

 Explain

the law of conservation of momentum

Momentum: A

quantity defined as the product of the mass and velocity of an object

 The

more momentum an object has the harder it is to stop the object or change its direction

Calculating Momentum:  Momentum

o o o o

(p)

p=mxv M = mass (kg) V = velocity (m/s) Momentum units = (kg • m/s) Momentum, like velocity, has direction

Math Focus  Text

page 167

 Momentum  Now

calculations…

its your turn #1-2

The Law of Conservation of Momentum  Any

time objects collide, the total amount of momentum stays the same

 True

for any collision if no other forces act on the colliding objects

 Applies

whether the objects stick together or bounce off each other

The Law of Conservation of Momentum

http://www.physast.uga.edu/~rls/1020/ch5/fig5-5.jpg

Objects Sticking Together 

Sometimes objects stick together after a collision



They will then move as one object



In a head-on collision the combined objects move in the direction of the object with the initial greater momentum



Mass and velocity change

Objects Sticking Together

http://www.physicsclassroom.com/mmedia/momentum/fca.gif

http://www.physicsclassroom.com/mmedia/momentum/fcb.gif

Objects Bouncing Off Each Other 

In some collisions, objects will bounce off each other



Momentum is usually transferred from one object to another



The result is the object move in different directions at different speeds



Total momentum remains the same

Objects Bouncing Off Each Other

http://www.codeproject.com/KB/recipes/GravitySimulation/GravitySimulation3.JPG

Conservation of Momentum & Newton’s 3rd Law  Action

– Reaction forces

http://simplethinking.com/teaching/newtonlaws_files/image002.jpg

Quick Quiz:  What  Give

is the equation for momentum?

an example of an object that has a large momentum. Explain your answer.