Work and Machines

The amount by which a machine multiplies an input force is called the _____.
1. fulcrum
2. mechanical advantage
3. resistance force
4. efficiency factor
Find the ideal mechanical advantage of the lever shown in this figure.
1. 5
2. 3
3. 1
4. 4
Sally and Pete do the same amount of work. Sally does the work in 2.3 hours and Pete does it in 2.5 hours. Who is using more power?
1. neither Sally nor Pete
2. Pete
3. Sally
4. both Sally and Pete
If you have to apply 130 N to the end of a screw driver used as a lever in order to lift a paint can lid held down by 520 N of force, what is the MA of your lever?
1. 1
2. 2
3. 5
4. 4
If the efficiency of a single fixed pulley like the one pictured were 100%, how much force would be needed to lift a weight of 63 N?
1. 37 N
2. 100 N
3. 163 N
4. 63 N
A machine cannot do which of the following?
1. multiply the input force
2. change the direction of a force
3. increase the speed of machine parts
4. create energy
How much work is done to push a 210 N box up a 12 m ramp if you have to push with a force of 70 N?
1. 840 J
2. 2520 joules
3. 280 joules
4. 840 watts
How much power is used by a student who lifts a book that weighs 11 N .75 m to the upper shelf of his locker in 2.0 seconds?
1. 4.1 W
2. 8.3 watts
3. 1.5 watts
4. 11 W
Actual mechanical advantage is less than ideal mechanical advantage because of _____.
1. gravity
2. work
3. friction
4. power
The fixed pulley shown below does which one of the following?
1. doubles the force required to lift the block
2. makes the block easier to lift by changing the direction of the force needed to lift it
3. decreases the force required and changes the direction of the force required
4. decreases the force required to lift the block
A bar that is free to pivot about a fixed point is a _____.
1. ramp
2. fulcrum
3. lever
4. screw
A slanted surface used to raise an object is a(n) _____.
1. screw
2. inclined plane
3. efficiency board
4. effort ramp
In an ideal machine, which of the following is true?
1. the IMA is always equal to one
2. work input is greater than work output
3. work input equals work output
4. work input is less than work output
An inclined plane with one or two sloping sides forms a machine called a _____.
1. wedge
2. pulley
3. ramp
4. lever
A device that does work with only one movement and changes the size or direction of a force is a(n) _____.
1. simple machine
2. compound machine
3. effort machine
4. screw
A machine that changes only the direction of a force has a mechanical advantage of _____.
1. 10
2. 5
3. 1
4. 100
In order for work to be done on an object, the object must _____.
1. be a machine
2. move
3. not move
4. be lifted
Two simple machines that are part of a bicycle are a(n) _____.
1. gear and a wheel and axle
2. inclined plane and a wedge
3. screw and an inclined plane
4. inclined plane and a lever
The rate at which work is done is called _____.
1. power
2. force
3. efficiency
4. effort time
When a machine is used to do work, the force applied by the machine is called the _____.
1. friction
2. output force
3. power
4. input force
If a weight lifter is holding barbells above his head, what does he have to do to perform work?
1. lower barbells
2. step forward
3. move barbells sideways
4. stand still
Three of the following simple machines are basically the same. The one that does NOT belong with the group is the _____.
1. pulley
2. wheel and axle
3. lever
4. wedge
Unlike a fixed pulley, a movable pulley _____ the effort force.
1. equals
2. multiplies
3. doesn't change
4. increases
An inclined plane wrapped around a cylindrical post is a _____.
1. lever
2. screw
3. block and tackle
4. ramp
Doorknobs and faucet handles are examples of a simple machine called a(n) _____.
1. wedge
2. tool
3. wheel and axle
4. inclined plane
A lever with a mechanical advantage greater than 1 is used to _____.
Your elbow is an example of what type of simple machine?
1. wedge
2. pulley
3. inclined plane
4. lever
Work, like energy, is measured in _____.
1. watts
2. newtons
3. joules
4. kilograms
The unit of power is the _____.
1. watt
2. second
3. joule
4. m/s
_____ is a measure of how much of the work put into a machine is changed to useful work put out by the machine.
1. Energy
2. A watt
3. Power
4. Efficiency
When a machine is used to perform a task, work output is always _____ work input.
1. less than
2. more than
3. equal to
4. unrelated
Reducing friction increases the _____ of a machine.
1. joules
2. ideal mechanical advantage
3. efficiency
4. power
The point about which a lever pivots is called the _____.
1. pulley
2. fulcrum
3. output arm
4. pivot point
In this figure, what is the ideal mechanical advantage of the inclined plane?
1. 3
2. 8
3. 12
4. 4
A winding mountain road is an example of a(n) _____.
1. lever
2. wheel and axle
3. inclined plane
4. block and tackle
A wheel and axle with teeth around the rim of the wheel is a _____.
1. pulley
2. compound machine
3. gear
4. wedge
A ramp for wheelchair access is what kind of simple machine?
1. inclined plane
2. wheel & axle
3. pulley
4. lever
When two or more simple machines work together, they are called a(n) _____.
1. effort machine
2. compound machine
3. simple machine
4. screw
A classroom pencil sharpener has a crank handle that is 5.0 cm long. The axle has a radius of .5 cm. What is the ideal mechanical advantage of the sharpener?
1. 10
2. 2.5
3. 5
4. 5.5
An arrangement of pulleys designed to reduce the effort force is called a _____.
1. movable pulley
2. block and tackle
3. simple pulley
4. fixed pulley

Work and Machines

Multiple-Choice ExerciseContent © 2006 Mary Jane Slaughter; Author of Activity: Tami Maloney; All rights reserved. No commercial, for-profit use of this material is allowed. E-mail comments and questions to Tami Maloney.

The amount by which a machine multiplies an input force is called the _____.

Find the ideal mechanical advantage of the lever shown in this figure.

Sally and Pete do the same amount of work. Sally does the work in 2.3 hours and Pete does it in 2.5 hours. Who is using more power?

If you have to apply 130 N to the end of a screw driver used as a lever in order to lift a paint can lid held down by 520 N of force, what is the MA of your lever?

If the efficiency of a single fixed pulley like the one pictured were 100%, how much force would be needed to lift a weight of 63 N?

A machine cannot do which of the following?

How much work is done to push a 210 N box up a 12 m ramp if you have to push with a force of 70 N?

How much power is used by a student who lifts a book that weighs 11 N .75 m to the upper shelf of his locker in 2.0 seconds?

Actual mechanical advantage is less than ideal mechanical advantage because of _____.

The fixed pulley shown below does which one of the following?

A bar that is free to pivot about a fixed point is a _____.

A slanted surface used to raise an object is a(n) _____.

In an ideal machine, which of the following is true?

An inclined plane with one or two sloping sides forms a machine called a _____.

A device that does work with only one movement and changes the size or direction of a force is a(n) _____.

A machine that changes only the direction of a force has a mechanical advantage of _____.

In order for work to be done on an object, the object must _____.

Two simple machines that are part of a bicycle are a(n) _____.

The rate at which work is done is called _____.

When a machine is used to do work, the force applied by the machine is called the _____.

If a weight lifter is holding barbells above his head, what does he have to do to perform work?

Three of the following simple machines are basically the same. The one that does NOT belong with the group is the _____.

Unlike a fixed pulley, a movable pulley _____ the effort force.

An inclined plane wrapped around a cylindrical post is a _____.

Doorknobs and faucet handles are examples of a simple machine called a(n) _____.

A lever with a mechanical advantage greater than 1 is used to _____.

Your elbow is an example of what type of simple machine?

Work, like energy, is measured in _____.

The unit of power is the _____.

_____ is a measure of how much of the work put into a machine is changed to useful work put out by the machine.

When a machine is used to perform a task, work output is always _____ work input.

Reducing friction increases the _____ of a machine.

The point about which a lever pivots is called the _____.

In this figure, what is the ideal mechanical advantage of the inclined plane?

A winding mountain road is an example of a(n) _____.

A wheel and axle with teeth around the rim of the wheel is a _____.

A ramp for wheelchair access is what kind of simple machine?

When two or more simple machines work together, they are called a(n) _____.

A classroom pencil sharpener has a crank handle that is 5.0 cm long. The axle has a radius of .5 cm. What is the ideal mechanical advantage of the sharpener?

An arrangement of pulleys designed to reduce the effort force is called a _____.

Multiple-Choice Exercise
Content © 2006 Mary Jane Slaughter; Author of Activity: Tami Maloney; All rights reserved. No commercial, for-profit use of this material is allowed. E-mail comments and questions to Tami Maloney.