Momentum
Calculating Momentum
Momentum Conservation
Momentum Change
Work
100
Momentum = Mass x _________
velocity
100
What is the momentum of a 60-kg halfback moving eastward at 9 m/s.
540 kg•m/s, east
100
F = mass x acceleration
Which of Newton's Laws does this represent?
Newton's 2nd Law
100
________ is a change in momentum.
impulse
100
Work can be calculated by...
W = Force x distance
200
The momentum equation shows that momentum is ___________ proportional to an object's mass.
directly
200
Momentum of a 1000-kg car moving northward at 20 m/s.
20 000 kg•m/s, north
200
True/False
For any collision occurring in an isolated system, momentum is conserved.
true
200
Which case has the greatest velocity change?
Case B
The velocity changes from +30 m/s to -28 m/s. This is a change of 58 m/s (-) and is greater than in case A (-15 m/s).
200
What are the units for Work?
Joules
300
True/False
An object's momentum is indirectly proportional to an object's velocity
false
300
A car possesses 20 000 units of momentum. What would be the car's new momentum if the velocity doubled?
40,000 units of momentum
300
A large truck collides with a small bicycle.
Finish the statement: The momentum before ...
...equals the momentum after
300
Which case has the biggest momentum change?
case B,
momentum change depends on velocity change
300
Find work done if a force of 30 moves a box 3 meters
90 Joules
400
The metric unit for momentum is ____________
kg x m/s
400
A car possesses 20 000 units of momentum. What would be the car's new momentum if its mass was doubled (by adding more passengers),
40,000 units of momentum
400
A small train moving 5m/s East collides with a large train moving 5m/s West.
What is the resulting motion?
West
400
Which case has the greatest acceleration change?
case A
400
Name another quantity that has the same units as Work.
KE
GPE
Heat
500
Momentum is a ______________ quantity with both magnitude and direction. (vector or scalar)
vector
500
A 60 kg quarterback is running at 3 m/s down the field.
A 90 kg halfback is running at 2 m/s down the field.
Which player has the most momentum?
neither, both players have the same momentum.
500
A 400kg train moving 2m/s East collides with a 200kg train moving 1m/s East. What is the final velocity?
p before = p after
(400 x 2) + (200 x 1) = 1000kgm/s
1000 = (400+200) x velocity
v = 1000/600
v = 1.67m/s
500
Which case has the greatest impulse?
Case A
impulse = momentum change, which depends on velocity change and velocity change is greatest in case A
500
How much work is done when a desk is lifted 3 meters high if the desk has a mass of 15kg?
F=15x10
F=150
W = Fxd
W = 150 x 3
W = 450J