This preview shows pages 1–3. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: Momentum
We deﬁned an object’s momentum:
Momentum of
the object = Mass of
the object × Velocity of
the object An object’s momentum is a measure of how hard it is
to stop or change the motion of the object. How do we change an object’s momentum?
By exerting a net force on the object for some period of
time. The more force and the longer time; the greater
the change in momentum. We deﬁne an impulse exerted on an object:
Net Impulse
on object × = Net Force
on object Time force
is applied = Change in Momentum
of object and:
Net Impulse
on object 1 Momentum, Impulse, and the Second Law
(optional for 11th Grade)
The Impulse  Change in Momentum Relationship is:
Net Impulse
on object = Change in Momentum
of object = Net Force = Fnet ∆ t. Since:
Net Impulse × Time interval We can call the Change in Momentum: m ∆v
Then (setting impulse equal to change in momentum):
Fnet ∆t = m ∆v
If I solve this equation for Fnet :
Fnet = m ∆v
∆t Remember the deﬁnition of acceleration? a =
So: ∆v
∆t Fnet = m a
So this ImpulseMomentum relationship is just a
restatement of the Second Law.
2 Collisions • Elastic Collisions
Collisions that don’t generate heat or deformation • Inelastic Collisions
Collisions that do generate heat and/or deformation • Totally Inelastic collisions
Collisions in which the objects couple together. Momentum is conserved in all collisions. 3 ...
View
Full
Document
This note was uploaded on 10/19/2011 for the course PHY 2020 taught by Professor Staff during the Spring '08 term at University of Florida.
 Spring '08
 Staff
 Physics, Mass, Momentum

Click to edit the document details