Ps 4.4.3 (Cst) Crash into me
100 J
How much work must be done on a 10-kg snowboard to increase its speed from 4 m/s to 6 m/s?
180 J
How much work must be done on a 24-kg shopping cart to increase its speed from 1 m/s to 4 m/s?
225000 J
How much work must be done on a 6000-kg stone car to increase its speed from 5 m/s to 10 m/s?
39.2 J
How much work will it take to lift a 2-kg pair of hiking boots 2 meters off the ground and onto a shelf in your closet?
120 kg-m/s
If a person has a mass of 60 kg and a velocity of 2 m/s, what is the magnitude of his momentum?
No
Has Mechanical energy that has been "lost" to friction actually been destroyed?
110 J
If gravity is the only force present, what is the total mechanical energy of a book falling off a shelf at a time when its potential energy is 50 J and its kinetic energy is 60 J?
27 J
If gravity is the only force present, what is the total mechanical energy of a glass of milk falling off a table at a time when its potential energy is 15 J and its kinetic energy is 12 J?
1200 W
If it takes 600 N of force to move a stalled truck 30 meters and you do it in 15 seconds, what is your power?
10
If the input force on a wheel and axle is 2 N and the output force is 20 N, what is its mechanical advantage?
10 N
If the input force on a wheel and axle is 2 N and the output force is 20 N, what is its mechanical advantage?
negative
If you push on a box but the box moves backward, you have done ________ work.
True
Setting a heavy suitcase down on the ground requires you to do negative work on it.
400 kg-m/s
A 2,500-kg car hits a fence with a force of 400 N, and the collision takes one second. What is the magnitude of its impulse?
Short time, large force
A car veers off course and runs straight into a brick wall. This is an example of which of the following?
20 kg-m/s
In an isolated system, Bicycle 1 and Bicycle 2, each with a mass of 10 kg, collide. Bicycle 1 was moving to the right at 5 m/s, while Bicycle 2 was moving to the left at 3 m/s. What is the magnitude of their combined momentum before the crash?
7,500 kg-m/s
In an isolated system, two cars, each with a mass of 1,500 kg, collide. Car 1 is initially at rest, while Car 2 was moving at 5 m/s. What is their combined momentum after the collision?
40,000 kg-m/s
In an isolated system, two cars, each with a mass of 2,000 kg, collide. Car 1 is initially at rest, while Car 2 was moving at 20 m/s. What is their combined momentum after the collision?
No
Is energy is the force that causes an object's displacement?
No
Is momentum the ability to do work?
No
Is rolling a cart up a ramp is an example of doing negative work?
No
When a person goes jogging and then stops, her kinetic energy is destroyed, leaving her with less energy than she had before?
Impulse-momentum theorem
Which of the following could be described as "impulse equals change in momentum"?
axe knife
Which of the following is a device that uses a wedge? A. doorknob B. axe C. knife D. baseball bat
Bicycle Doorknob
Which of the following is an example of a device that uses a wheel and axle? A. bicycle B. doorknob C. frisbee D. light bulb
A car driving along the freeway A child riding a bicycle down the street
Which of the following is an example of kinetic energy? A. A car driving along the freeway B. A bike parked at the top of a hill C. A book on a shelf D. A child riding a bicycle down the street
A glass of water sitting on a table A rock teetering at the edge of a cliff A vase on the top shelf
Which of the following is an example of potential energy? A. A child running across a field B. A glass of water sitting on a table C. A rock teetering at the edge of a cliff D. A vase on the top shelf
Force = 6, Time = 3
Which of the following is equal to an impulse of 18 units? A. Force = 6, time = 3 B. Force = 10, time = 2 C. Force = 7, time = 3 D. Force = 0.1, time = 18
A person jogging around a lake A car driving along the freeway
Which of the following is not an example of potential energy? A. A person jogging around a lake B. A glass of water sitting on a table C. A car driving along the freeway D. A book on a shelf
500 N
You expend 1000 W of power in moving a piano 10 meters in 5 seconds. How much force do you exert?
1,000 N
You expend 1000 W of power in moving a piano 5 meters in 5 seconds. How much force did you exert?
2,000 J
You push a piano 5 meters across the floor with a force of 400 N. How much work have you done?