Momentum
Conservation of Momentum
Energy
Conservation of Energy
Potpourri
100
Momentum = __ x __
mass x velocity
100
TRUE or FALSE?
Bouncing objects have greater impulse than ones of equal mass and velocity that don't bounce.
TRUE
100
Energy is the ability to do __.
work
100
Daily Double!
The law of conservation of energy says that...
1) "energy CANNOT be __ or __"
2) but it CAN be __
1) created or destroyed
2) changed
100
Daily Double!
A rock at the top of a tall cliff has a potential energy of 5,000 Joules. What is its...
1) kinetic energy at the top of the cliff?
2) kinetic energy when it hits the ground below?
1) 0 J
2) 5,000 J
200
Daily Double!
1. Impulse = __ x __
2. Impulse is a __ in momentum
1. Force x time
2. change
200
Give your own 1-3 word definition of "conservation."
Stays the same
Remains unchanged
Does not change
200
Daily Double:
1) what is the SI unit for energy (work)?
2) Break this unit down into kg, m, and s.
1) Joules (J)
2) kg m2/s2
200
What is the mechanical efficiency of a machine that puts out 40 J of electrical energy for every 80 J of stored chemical energy it has in its battery?
50%
200
There are 2 race cars of identical mass, but one of them travels 3 x as fast. What is its kinetic energy compared to the slower car?
32 = 9 x the KE
300
What is the momentum of a 250 kg object moving with speed of 4 m/s?
1,000 kg m/s
300
Give the law of conservation of momentum in equation form.
mvbefore = mvafter
300
Daily Double:
1) What is the SI unit for power?
2) Break this unit down into kg, m, and s.
1) Watts (W)
2) kg m2/s3
300
Give the law of conservation of energy (work) in equation form.
Fdinput = Fdoutput
300
Name for a collision where objects stick together after they collide
Inelastic
400
What is the force on an object that has a mass of 5 m traveling 3 m/s that comes to rest in 0.1 s?
150 N
400
A 4 kg object moving at 5 m/s collides with, and sticks to a 6 kg object at rest. What is the speed of the objects after the collision?
2 m/s
400
What is the gravitational potential energy of a 6 kg object resting on a 5 m tall platform?
300 J
400
This thing demonstrates conservation of energy. It is called Newton's __.
(Funny answers may receive points)
Newton's cradle
400
A 100 N force is applied to a car jack lever that is 1 m long. The output force on the car to lift it is 10,000 N. How high does the car go up in this scenario?
0.1 meters (0.1 m)
1 decimeter (1 dm)
10 centimeters (10 cm)
500
A force of 10 N is applied over 2.5 s and the object travels 5 m/s. What is the mass of the object?
5 kg
500
A big fish is 3 x larger than a small fish, and they are swimming at each other. The big fish is traveling 3 m/s, and the small fish is traveling 1 m/s. The speed of the big fish after it eats the small fish is __.
2 m/s
500
What is the kinetic energy of a 3 kg object moving 10 m/s?
150 J
500
What distance does a 2 kg object move if it is traveling 2 m/s when a 2 N force is applied to it? (Hint: work-energy theorem)
2 m
500
Two identical cars (mass of 1500 kg) collide at a 90o angle in an intersection. Both are traveling 15 m/s. What is the resultant velocity after they collide?
10.6 m/s