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Physics 1050
Laboratory #5 Momentum and Impulse
Momentum and Impulse
Momentum:
Momentum is a vector defined as the product of an object’s mass m
!
and velocity v
!
!
p = mv .
Momentum is a vector and has the same direction as the velocity. It
has units of kg⋅m/s. If a system has more than one object, the total
momentum is the sum of the momentum of each object.
If there is no external force applied to the system, momentum is
conserved and the total momentum of the system before a collision
!
!
equals the total momentum after a collision: pbefore = pafter .
If there is an external force applied to the system, momentum is not
conserved and the total momentum of the system before a collision
!
!
does not equal the total momentum after a collision: pbefore ≠ pafter .
Impulse:
When a force is applied to an object over a time interval, the force will
accelerate the object thus changing the object’s velocity, and
therefore the object’s momentum.
We define the impulse I to be the change in momentum of the object.
!
!
!
I = mv2 − mv1
! !
= p2 − p1.
Impulse is also given as the product of force with time
! !
I = FΔt .
For an object moving at constant velocity, the slope of the object’s
Position versus Time curve is its velocity.
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Physics 1050
Laboratory #5 Momentum and Impulse
Prelab Questions
These questions need to be completed before entering the
lab. Show all workings.
Markers
Initials
In experiment 5, you will push one cart towards another stationary cart. They will
collide, stick, and move together.
Prelab 1:
Write the equation for the total momentum before the collision.
Write the equation for the total momentum after the collision.
Prelab 2:
If we have that m1 = 0.500 ± 0.005 kg, m2 = 1.000 ± 0.005 kg,
v1 = 0.25 ± 0.01 m/s, and vf = 0.07 ± 0.01 m/s, calculate the initial
and final momentum and the impulse. Include uncertainty with each
calculation.
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Physics 1050
Laboratory #5 Momentum and Impulse
Name and Student Number:
___________________________________
Date:
___________________________________
Partner:
___________________________________
Part I :
Introduction
Part II:
Conservation of Momentum
Table 1:
Masses of Cart 1 and block.
Mass
Uncertainty
Units
Uncertainty
Units
Cart
Block
Plastic Card
Total mass
Table 2:
Masses of Cart 2 and blocks.
Mass
Cart
First block
Second block
Total mass
QUESTION 1:
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Physics 1050
CHECKPOINT:
Table 3:
Laboratory #5 Momentum and Impulse
To be signed after making your first graph.
Time of collision.
Time
Units
Collision
Table 4:
Initial and final velocity.
Velocity
Uncertainty
Units
Uncertainty
Units
Initial
Final
Table 5:
Initial and final momentum.
Value
Initial momentum
Final momentum
Impulse
Show calculations here.
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Physics 1050
QUESTION 2:
QUESTION 3:
QUESTION 4:
QUESTION 5:
Laboratory #5 Momentum and Impulse
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Physics 1050
Laboratory #5 Momentum and Impulse
QUESTION 6:
Table 6:
Initial and final momentum of cart 1.
Momentum
Uncertainty
Units
Initial
Final
Show calculations here.
Table 7:
Initial and final momentum of cart 2.
Momentum
Initial
Final
Show calculations here.
Uncertainty
Units
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Physics 1050
Table 8:
Laboratory #5 Momentum and Impulse
Impulse
Impulse
Cart 1
Cart 2
QUESTION 7:
Part III:
Summary
QUESTION 8:
Uncertainty
Units
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Physics 1050
Laboratory #5 Momentum and Impulse
QUESTION 9:
Return to the lab manual:
Staple graph to the reverse
of this page.