Work and Power

The metric unit for work is the ____.
1. newton
2. joule
3. watt
4. meter
If forces Red, Blue and Green are equal, the work done by the forces as they are exerted on the box is ____.
1. greatest for force Red
2. greatest for force Blue
3. greatest for force Green
4. the same for all forces
A unit used to measure power is the ____.
1. joule
2. newton-meter
3. newtons per second
4. watt
An automobile jack exerts a force of 4,500 newtons to raise a car 0.25 meters. The amount of work done by the jack is about ____ joules.
1. 0.00056
2. 1,100
3. 4,500
4. 18,000
A 60-newton block at rest at the bottom of a frictionless incline plane is pushed up the incline. The amount of work done against gravity is ____ joules.
1. 0
2. 20
3. 60
4. 180
A 2.2-kilogram crate is pulled by a 30-newton force over a distance of 5 meters. The work done by pulling the crate is ____ joules.
1. 11
2. 66
3. 150
4. 330
The action that would require no work to be done is ____.
1. holding a 100-pound object over your head
2. pushing a 25-kilogram box of books across the floor
3. pedaling a 100-newton bicycle up a small hill
4. lifting a balloon filled with air from the floor to a desktop
When a force applied to an object causes the object to move in the direction of the force, the object acquires ____.
1. energy
2. mechanical advantage
3. efficiency
4. friction
Running up a flight of stairs, Maria generates 450 watts of power. If it takes her 6 seconds to go up the stairs, the amount of work she does in running up the stairs is ____ joules.
1. 0.013
2. 75
3. 450
4. 2,700
Jasmine, who weighs 400 newtons, moves up a 5.0-meter climbing wall in 15 seconds. The amount of power generated by Jasmine as she climbs the wall is about ____ watts.
1. 130
2. 2,000
3. 6,000
4. 30,000
60 joules of work are required to lift the 10-newton object 5.0 meters as shown in the diagram. The amount of work done in overcoming friction as the weight is lifted is ____ joules.
1. 10
2. 50
3. 60
4. 300
The diagram shows a 20-newton force being used to pull a 5-kilogram object up a hill at a constant speed. The amount of work done against gravity in moving the object from point A to point B is about ____ joules.
1. 100
2. 200
3. 500
4. 600
Jordan lifts a 100-kilogram barbell from the floor to a height of 2.0 meters in 1.5 seconds. The amount of power he generates is about ____ watts.
1. 130
2. 200
3. 1,310
4. 1,960
An electrical water heater raises the temperature of water by adding 8,000 joules of energy to the water in 40 seconds. The minimum power that must be supplied to the heater is ____ watts.
1. 0.005
2. 200
3. 3,200
4. 320,000
Josephine slides a 150-newton box 12 meters up an incline plane. If the incline plane lifts the box 4 meters as she pushes with a 60-newton force, the work input done by Josephine is ____ joules.
1. 48
2. 600
3. 720
4. 9,000
What does the value “100 newtons” represent?
1. mass
2. distance
3. force
4. speed
What does the value “1.5 meters” represent?
1. mass
2. distance
3. force
4. speed
Which equation would allow you to calculate the work done on the barbell?
1. red
2. green
3. blue
4. purple
How much work is done on the barbell?
1. 0.015 joules
2. 15 joules
3. 66.7 joules
4. 150 joules
In science, work is defined as ____.
1. the mass of an object multiplied by its acceleration
2. the mass of an object multiplied by the force required to move it
3. force divided by the distance moved in the same direction as the force
4. force multiplied by the distance moved in the same direction as the force
Work may be measured using units of ____.
1. watts
2. newtons
3. joules
4. newtons / second
The SI unit for power is ____.
1. newton
2. joule
3. watt
4. kilogram
One watt is equivalent to one ____.
1. N/s
2. N•s
3. J/s
4. J•s
What is the power of a light bulb that produces 50 J of work in 2.0 s?
1. 100 W
2. 75 W
3. 50 W
4. 25 W
The transfer of energy that results from applying a force over a distance is called ____.
1. work
2. power
3. momentum
4. collisons
If Sam pushes a block one meter with a force of one newton, he has done one ____ of work on the block.
1. joule
2. watt
3. newton
4. kilogram
For an object to do work, it must possess ____.
1. energy
2. inertia
3. mass
4. volume
The work Brandon does in lifting a rock is calculated by multiplying the weight of the rock by the change in the ____ of the rock.
1. height
2. mass
3. volume
4. color

Work and Power

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