| A | B |
|---|
| When you hold a bag of groceries, | you are not doing work. |
| The force exerted by a machine | is called the input force |
| mechanical advantage is | the number of time a machine increases a force exerted on it |
| A machine makes work easier by reducing the amount of work needed to do the job | False |
| In order for you to do work on an object, the object must move some __________ as a result of your force. | distance |
| A machine ________the amount of out put force | increases |
| Why is no work done when you carry an object at a constant velocity? | since the force is verticle and the motion is horizontal, you don't do any work on the object as you carry it |
| The _________ is a fixed point that | fulcrum |
| When you push on a stuck car | you are not doing work |
| what is a machine. | a device that allows you to do work in a way that is easier or more effective |
| The longer the inclined plane, the less __________ you need to push or pull an object | force |
| The amount of work you do depends on both the amount of _______ you exert and the ______ the object moves | force distance |
| Lifting a heavier object demands greater _____ than lifting a lighter object | force |
| A _____________allows you to exert your force over a longer distance | inclined plane |
| When is work done on an object | When it moves |
| In a _______the inclined plane itself | wedge |
| A simple machine made of a grooved wheel with a rope or cable wrapped around it is | a pulley |
| A way that a machine makes work easier by multiplying the ______ over which you exert force | distant |
| When you pull your books out of your book bag you are | doing work |
| You have greater ________when you run up a flight of stairs than when you walk | power |
| The _____ and _____ a wedge is, the greater it's mechanical advantage | longer and thinner |
| In a machine that has a mechanical advantage of more than 1, the ______ force is greater than the _____ force | input force is greater then the output force |
| A simple machine made of two circular or cylindrical objects fastened together that rotate about a common axis is a | wheel and axle |
| A spiral inclined plane forms the __________ of a screw | threads |
| What kind of pulley has an ideal mechanical advantage of 2 | a movable pulley |
| What do most levers in your body consist of | bones and muscles |
| Work = Force X Distance is __________. | the amount of work done |
| In some machines, the _____ force is greater than the ____ force. | output force greater than input force |
| The necessary input force is less than the output force. T or F | false |
| The rate at which work is done is | power |
| When you hold a heavy piece of wood you are | not doing work |
| A flat slope surface is a | inclined plane |
| The force you exert on a machine is called the _______ force | input force |
| A ramp is an example of an | inclined plane. |
| A machine that utilizes two or more simple machines is a | compound machine |
| What are the three classes of levers | first, second, third |
| A(n) __________ plane is a flat, slanted surface | inclined |
| The force you exert on a machine is called the | input force |
| A rigid bar that is free to pivot, or rotate, about a fixed point is a _________. | lever |
| Why does only part of your force do work when you pull a suitcase with wheels | only part of your force does the work |
| If the object does not move, ________ is done no matter how much force is exerted | no work |
| One way a machine makes work easier by changing ___ _______ in which you exert force | the direction |
| The ________ is not always located at the same place on a lever | fulcrum |
| Three ways in which a machine can make work easier for you ( ADD). | amount of force, distance over and direction you exert your force |
| The force exerted by the machine is called the ________ ______. | output force |
| The __________ of a machine compares the output work to the input work | efficiency |
| A grooved wheel with a rope wrapped around it is a(n). | pulley |
| In a living lever in your body, what acts as the lever’s fulcrum? | your joints |
| A device with which you can do work in a way that is a _________. | machine |
| What kind of pulley changes the direction of the input force but does not change the amount of the force you apply? | a fixed pulley |
| In order for you to do work on an object, the object does Not have to move some distance as a result of your force.T or F | false |
| How does your front teeth are like an ax. | they cut through your food |
| A screw can be though of as an _______ plane | inclined |
| The mechanical advantage of a machine without friction is called the machine's ______ mechanical advantage | ideal |
| A machine makes work easier by multiplying the force you exert. T or F | True |
| A lever changes the direction of your input force. T or F | True |
| What is the SI unit of work? | Newton X meter |
| The SI unit of work is called the __________. | Joule |
| A screw, eggbeater stapler, fishing pole, siccors, and a hole puncher are basic types of _____ ______. | simple machines |
| A machine that utilizes two or more simple machines is called a ________ machine | compound |
| The mechanical advantage that a machine provides in a real situation is called the ________ mechanical advantage. | actual |
| What is the amount of work you do when you exert a force of 1newton to move an object a distance of 1 meter? | Newton X Meter |
| The force you exert on the machine is callled the ______ force | input |
| The force the machine exerts on an object is called the _____ ______. | output force |
| In any machine, some work is wasted overcoming _____ of _______. | force of fiction |
| Efficiency is not expressed as a percent. T or F | false |
| A lever increases and _____ ______ of your input force | changes direction |
| A machine is a device that does ALL the work for you. T or F | false |
| If a machine allows you to use less force to do some amount of work, then you must apply the input force over a greater ___________. | distance |
| When twisting a screw into a piece of wood, where is the input force applied and where is the output force exerted? | Input on the screw, and output on the wood |
| Your muscles are attached to your bones by tough connective tissues called ________. | tendons |
| What kind of pulley has an ideal mechanical advantage of 1 ? | a fixed pulley |
| What kind of pulley has an ideal mechanical advantage of 3 ? | block and tackle |
