Momentum
Which of Newton's Laws does the impulse momentum theorem come from?
What is Newtons Second Law!
Define Conservation of momentum in words, not an equation.
What is the total momentum of all objects interacting with one another remains constant regardless of the nature of the forces between the objects.
Define an Elastic collision
What is an event when two objects completely rebound off one another. Both Momentum and Energy are conserved.
What two ways can an impulse change an objects momentum?
What is magnitude or direction.
A loaded railway car of mass 5000kg is rolling to the right at 2m/s when it collides and sticks to an empty railway car of mass 2000 kg rolling to the left on the same track at 3 m/s. What is their speed and direction of the pair after the collision?
What is .57m/s right.
This is the main difference between elastic and inelastic collisions.
What is The conservation of both momentum and Kinetic energy.
A 2kg skateboard is rolling across a smooth, flat floor when a girl kicks it, causing it to speed up to 4.5m/s in 0.5s without changing direction. If the average force exerted by the girl on the skateboard in its direction of motion was 6N, with what initial velocity was it moving?
What is 3 m/s
A boy on a 2.0kg skateboard initially at rest tosses an 8.0kg jug of water in the forward direction. If the jug has a speed of 3.0m/s relative to the ground, and the boy and skateboard move in the opposite direction at .60m/s, find the boy's mass.
What is 38kg.
Give me an example of an action reaction situation.
What is A bullet leaving a gun, a cannon and cannonball, ball bouncing, person jumping, etc...
Which object has more impulse: a bullet hitting a block with a force of 70N over .3s, or a hockey stick exerting 120N of force on a puck for .05s.
What is the bullet with a impulse of 21N*s
A 4.0 kg soccer ball approaches a player horizontally with a velocity of 18m/s to the north. The players strikes the ball and causes it to move in the opposite direction with a velocity of 22m/s. What impulse was delivered to the ball by the player?
What is 16 kg*m/s to the south.
Sometimes the curiosity factor at the scene of a car accident is so great it actually produces secondary accidents as a result, while people watch to see what is going on. If an 800 kg Sports car slows down to 13m/s to check out an accident scene and is rear ended by a 1200 kg pickup truck traveling at 25m/s. The bumpers of the vehicles lock and the two vehicles move off together as one unit. What is the post collision velocity.
What is 20.2m/s
Which object has more momentum? A 50 kg object moving at 10m/s or a 2.5 kg object moving at 200m/s
What is their momentum is equal.
Cars have air bags in the steering wheel and on the sides. What is the purpose of these air bags related to impulse.
What is to increase the time the person undergoes the impact.
When a force is exerted on an object, does a large force always produce a larger change in the objects momentum than a smaller force does? Explain. Hint: think about time.
What is no, because the change in momentum = F*t, it is possible for a lage force applied over a very short time interval to change the momentum less than a smaller force applied over a longer time period.
A spacecraft undergoes a change of velocity when its rockets are fired. How does the spacecraft change velocity in empty space where there is nothing for the gases emitted by the rockets to push against?
What is The principle of conservation of momentum tells us that the momentum of the space craft and its fuel before the rockets are fired must equal the momentum of the two after the rockets are fired. Both begin at rest so our total initial momentum is zero. When the rocket is fired, the combustion of the fuel gives the exhaust gases momentum. The spacecraft will gain a momentum equal in magnitude but opposite in direction of the exhaust gases. Thus the total momentum will be kept zero.
If two cars collide, they usually do not stick together. Does this mean the collision is elastic?
What is no, some KE is converted to sound energy and some is converted to internal elastic potential energy as the cars deform, so the collision can not be elastic.