Chapter16-+Simple+Machines

=**//__Chapter 16 Simple Machines__//**=

Simple machines are used to perform tasks (work). **__ALL__** machines help us do work. Work means using force (push or pull) in order to move an object. The heavier the object the __**more**__ force you must use to move it. Some simple machines allow us to use less force to do the work. ex. a jack to pick up a car.

Simple Machines: Lever Pulley Inclined Plane Wedge Wheel and Axel Screw

Lever- a simple machine with a long bar that has a support.

Load- the object you want to move

Effort- push or pull on a bar

A lever doesn't make you stronger, but it does make work easier. It takes the same effort to lift a heavier object when the load is closer to th fulcrum.

__Wheel and Axle-__ A special kind of __lever__ that moves or turns objects. __Pulley__- wheel and rope,chain,or wire around it.the load hangs from a hook when you pull down (force and effort) on the rope,the end of the load will go up.

1.A pulley can change the dirction of a force.

2.A pulley can decrease the amount of force needed to move a load.

How is a wheel and axle similar to a lever? Wheel and axle is a special kind of lever. Both are simple machines that move around a fixed point. The lever moves around a fulercrum,and a wheel moves around axle.

__LESSON 2 How can machines work together__ A Ramp is a simple machine called an inclined plane. It is easier to slide a heavy object up a smooth inclined plane then to lift the object straight up. It takes less force to move that object.If 2 ramps are the same height more force is required.

1.The length of the ramp and the how steep it is has an effect on the amount of force needed.

2.Friction can slow things down. Friction makes it harder to push,pull, or drag things.stronger a force is,the faster it will move an object. an object that is moved over the greater distance (the longer,flatter (not as steep) Inclined plane requires less force.

3/8/11 A __wedge__ is a special kind of inklined plane.wedges can be used to split things. 1. A force aimed at the end of the inclined plane makes it move. 2. wedges can be used to hold things in place. 3.a wedge can also be used to stop a much larger object from moving screw-a special type of inclined plane. (the ridges in the screw are called threads) 1.fasten things (holds things together better than a nail because of the threads.) (it rquires less force than a nail.) 2.can lift things. __Complex machines__ are made of __many parts__ and often include several kind of __simple machines__ working together. complex machines can be powered by __muscle power__ or other sources of power such as electricity.

Test Prep Review

1.fulcrum 2. screw 3.Wedge 4. pulley 5.effort 6.wheel and axle 7.inclined plane 8. lever 9. load

10. If the fulcrum is closer to the effort, more force is needed to move an object than when the fulcrum is in the middle. However, if the fulcrum is closer to the load, less force is needed to move the same object.

11. A simple machine differs from a complex machine because a simple machine consists one or two parts while a complex machine may have any number of parts some of which are simple machines.

12. They are alike because wegdes and screw are types of inclined planes. A wedge is a special type of inclined plane that can be used to split things apart, hold things in place, or move things. A screw is an inclined plane rapped around a rod that can be used to fasten things and to lift things up.

13 . One carmenter may prefer to use nails. Even though pounding a nail takes alot of effort, it does not need to be pounded many times. Another carpenter might prefer screws because even though it takes many turns, you can use less force.

14. The first one are pliers. Pilers is a SIMPLE MACHINE. The second one is inside of a watch. It is a COMPLEX MACHINE. The thrid one is a broom, it is a SIMPLE MACHINE. The forth one is a bicycle. It is a COMPLEX MACHINE.

15.Details:A lever is a long bar with support called the fulcrum. Details:A lever is a simple machine. Details:You must apply effort to a lever to move a load. Summery: A lever makes doing work easier because it adds to the amount of force or decreases a worker must use.

16.A 17.H 18.D 19.A. is the best choice because in science, work means using force on something and moving a distance, B. is not complete because it does not talk about force. C. would be a good definition,for everyday life but it is not the special scientific definition. D. is incorrect because it leaves out moving a distance

Chapter 1 lesson 1 quick study

1.Cells are considered the building blocks of all living things because a cell is the smallest part of a living thing and all living things are made of cells.

2. A group of cells working together to do some job or __tissue.__ A group of tissues working together to the job are called organs.

3. A single organism has only __one__ you would need a group of simular cells working together in order to have tissue.

Animal cell Plant cell Kindoms: Ancient Bacteria Protists Fungi Plant Animal
 * Animal cells || BOTH || Plant cells ||
 * || nucleus cytoplasm cell membrane building blocks of life || chloroplasts cell wall ||

Chapter 1 Lesson 2 Quick study

1. A classification system is important to scientists because the world has over a million kinds of organisms. A classification is used to identify to compare and to study them.

2. Scientists classify organisms based on (1) how many cells it has (2) where it lives (3) how it gets it's food.

3. Living things that make it's own food can be found in the plant kindom ancient bacteria kingdom some true bacteria and protists also make ther own food.

Chapter 1 Lesson 3 Quick study

1. Some examples of vascular plants are grass,celery,and trees.

2. Conifers are plants that make seeds but do __not__ have flowers. The seeds grow in cones. Example: evergreen trees like pincones.

3.One way of classifying plants into groups is how they move food and water. Another way biologists classifying plants is by how they make new plants.

4.
 * One Cell ||  ||   ||   ||