Keep the momentum going!
Impulsive decisions
Control the impulse-momentum
Glad we could bounce ideas off each other
Apply this
100
What is the SI unit for momentum?
p=mv
100
Define impulse
Impulse is the product of force and the time period over which it acts.
100
What does the impulse-momentum theorem state?
The impulse acting on an object is equal to the change in momentum of the object.
100
Describe an elastic collision.
An elastic collision is where both momentum and kinetic energy are conserved.
100
Why are cars designed with crumple zones to increase safety? Use the words time, force, and momentum in your answer.
Crumple zones increase the time it takes for momentum to change thereby reducing the force experienced during the collision. Less force means less injury.
200
Calculate the momentum of a 500 kg motorcycle that is traveling at 20 m/s.
p=500 kg x 20 m/s = 10,000 kg*m/s
200
A force of 25 N is applied for 3 seconds. What is the impulse?
80 N*s
200
A 2,000 kg car experiences a 10,000 Ns impulse. What is its change in velocity?
5 m/s
200
Two identical balls collide elastically. If one is stationary and the other moves at 5 m/s, what are their velocities after the collision?
The moving ball stops, and the stationary ball moves at 5 m/s.
200
How does conservation of mommentum apply to rocket launches?
Rockets expel gas downwards, and by conservation of momentum, the rocket moves upward
300
Calculate the velocity of an 80,000 kg jetliner with a momentum of 640,000 kg*m/s
Velocity = 640,000 kg*m/s / 80,000 kg = 8 m/s
300
How long must a force of 10,000 N be applied to generate an impulse of 500,000 N*s?
Time = 50 seconds
300
How can you decrease the momentum by changing the impulse?
Impulse changes momentum by applying a force over a time interval, resulting in a change in velocity. If you want to decrease momentum, you either need to decrease the force or increase the amount of time.
300
Ball 1 is 2 kg and moving at 3 m/s. Ball 2 is 3 kg and at rest. They collide elastically. What is the final velocity of Ball 1?
-0.6 m/s
300
How do boxing gloves reduce the impact of a hit?
Boxing gloves are padded to increase contact time, therefore reducing force
400
A wheelbarrow's mass is halved. If its intial momentum was 137 kg*m/s, what is its new momentum if velocity remains constant?
1/2 * 137 kg*m/s = 68.5 kg*m/s
400
If an airbag applies an impulse of 150 N*s in 0.02 seconds, what force does it exert?
5,000 N
400
A 2,000 kg SUV moving at 15 m/s needs to stop in 6 seconds. What force is required?
5000 N
400
Ball 1 is 2 kg and moving at 3 m/s. Ball 2 is 3 kg and at rest. They collide elastically. What is the final velocity of Ball 2?
2 m/s
400
Why do airplanes use drag mechanisms during landing?
Slowing the velocity (speed) before a final, sudden impact reduces the force that the plane will land on the ground with thereby lowering the momentum.