Show:
Work & Power
Energy
Momentum & Impulse
Conservation of Momentum
Miscellaneous
100
What is the work done by a man who pushes a box forward 10 m with a 25 N force in the direction of motion?
250 J
100
What is the kinetic energy of a 120 kg horse galloping at 6 m/s?
2160 J
100
Which has a larger momentum a 2 kg ball with a speed of 30 m/s or a 200 kg motorcycle with a speed of 1 m/s?
The motorcycle.
100
Identify the type of collision: A train collides with another train at rest, the two couple together and move forward as one.
An inelastic collision.
100
The change in momentum of an object is also know as what?
Impulse
200
What is the work done by a woman who pulls a 5 kg suitcase at an angle of 40 degrees with a force of 20 N for a distance of 100 m?
1532 J
200
What is the mechanical energy of a 60 kg person falling at a speed of 10 m/s at a height of 7 m?
7116 J
200
What is the impulse of an 10 kg object that goes from 2 m/s to 40 m/s?
380 kg*m/s or N*s
200
If a 50 kg ice skater is moving forward at 5 m/s and her 60 kg partner is is moving towards her at 4 m/s. What will be their total momentum after they collide?
10 kg*m/s
200
What is Mr. Williams' favorite color?
He doesn't have one.
300
What is the power exerted by a 40 kg person who walks up a 3 m flight of stairs in 15 seconds?
78.4 W
300
What is the work done by a car's engine on a 1500 kg car that speeds up from 10 m/s to 25 m/s?
393,750 J
300
What is the force acting on a 0.02 kg golf ball that accelerates from rest to 200 m/s in a time of 0.001 seconds?
4000 N.
300
A 1000 kg truck moving at 10 m/s collides with a 400 kg car moving at 14 m/s in the opposite direction. If the trucks velocity after the collision is 2 m/s in it's original direction what is the speed and direction of the car after the collision?
6 m/s in the direction the truck travels.
300
A 90 kg halfback runs north and is tackled by a 120 kg opponent running south at 4 m/s. The collision is perfectly inelastic. Just after the tackle, both players move at a velocity of 2 m/s north. Calculate the velocity of the 90 kg player just before the tackle.
10 m/s
400
What is the work done by friction if a person pushes a 3 kg box forward 15 m at a constant velocity with a force of 18 N applied at an angle of 20 degrees above the horizontal?
-253.7 J
400
A 1 kg sugar glider is gliding at a speed of 3 m/s at a height of 15 m. How fast would would the sugar glider be traveling if its height drops to 5 meters.
14.3 m/s
400
What is the change in momentum of an 2 kg object that falls from rest (on earth) for 4 seconds?
74.8 kg*m/s
400
A 4 kg hunk of clay is hurled at an 10 kg toy car initially at rest. The clay hits the car and the two move off with a speed of 6 m/s. How fast was the clay initially thrown at the car?
21 m/s
400
An 2 kg object is initially at a speed of 5 m/s and a height of 2 m. Some time later the object is at a height of 40 m and a speed of 8 m/s. What was the work done on the object?
783.8 J
500
The maximum hp a 80 kg person can produce is 0.7 hp. How high would this person go running up a flight of stairs for 1 minute. (1 hp = 746 W)
40 m.
500
A 15000 kg roller coaster descends from an initial height of 200 m, starting from rest. When it is at a height of 90 m what is its potential energy, kinetic energy, mechanical energy, and speed? Answer in scientific notional with 3 sig figs.
PE = 1.32 x 10^7 J KE = 1.62 x 10^7 J ME = 2.94 x 10^7 J v= 46.4 m/s
500
What is the final velocity of a 2000 kg car that accelerates from 4 m/s with a force of 500 N for 20 seconds?
9 m/s
500
A kid is skateboarding on a 2 kg skate board at a speed of 5 m/s. He jumps off and moves forward at a speed of 3 m/s while the skateboard moves forward with a speed of 30 m/s. What is the mass of the kid?
25 kg
500
A 5 kg object at rest undergoes an impulse of 300 N*s over a time of 2 seconds and over a distance of 10 m. What is the work done on the object over this time & what is it's finial velocity?
W = 1500 J v = 24.5 m/s