Machine Chart: Complex Machines

We have now completed our "Machine Chart" of simple machines. The last column however is for Complex Machines. Complex machines are simply any machine with two or more simple machines combined.

They do not have to be big to be complex. For example, the axe is a complex machine because the handle works as a lever & the cutting edge is a wedge. So the two simple machines working together make this a complex machine.

There are many complex machines around you that are used in your home & yard. Some examples are the lawn mower, washing machine, & vacuum cleaner. They are also used in your community: like machines in factories used to make things or the trucks that carry food to the grocery store.

In your final column on your chart list a variety of complex machines. Look all around you to find as many as you can. Think of forms of transportation, what keeps your house cool in the summer or warm in the winter, & what machines are used on a construction site, etc. While you are searching for complex machines, keep your eyes open for more simple machines that you may have missed & add them to your other columns.

This ends our "Machine Chart" project. I hope you learned about machines & how useful they are!

Simple Machines: Pulleys!

On to the last column of our simple machines: Pulleys! My son said, "I love pulleys, I don't know why." Maybe it is because pulleys are fun! When you see a flag raised up the flagpole it is being pulled up with pulleys.

A pulley is a wheel with a groove in its edge. A rope fits into the groove. When the rope is pulled, the wheel turns. Anything attached to the end of the rope (the load) is moved. There are two kinds of pulleys: a fixed pulley & a block and tackle.

A fixed pulley is attached (like the flag pole) & can only be moved in one direction...as in up & down. In the block & tackle there are two or more pulleys...one is fixed & the other is attached to the load (or the item being moved). These pulleys are the block & the ropes that connect them is called the tackle. The more ropes & pulleys used the easier the job will be.

Sometimes it is hard to recognize pulleys around you. Here are some other examples that maybe you have not thought of. Curtain rods, tow trucks, mini-blinds, & cranes. Draw or cut out photos to paste to your chart. Look around & list as many as you can on your chart.

As you see on your chart there is one last column left empty. We will be working on that later but as for now we are done with our columns of the six simple machines. I hope you had fun...check back to finish the last column.

Simple Machines: Wheel and Axle

Next column on our Machine Chart is the Wheel & Axle. We just talked about screws in our last column, but what would a screw be without a screwdriver? That's right...a screwdriver is a type of wheel & axle. The axle (rod) fits into the head of the screw & the handle serves as the wheel as it turns. Your hand supplies the force.

The wheel by itself is just a roller. It is useful because it can help do work with less friction, but it is not until you connect it to an axle does it really become a useful machine. Of course we automatically think of cars when we think of the wheel & axle...what others can you think of?

How about a doorknob? The rod through the door is the axle & the knob is the wheel. Once again your hand supplies the force & they all work together to move the latch. Wheel & axles move things easily & help make work easier to do.

Some other objects that fall under this category are gears. Gears are sets of wheels that work together. One wheel can work another wheel if they are notched together. When my son was little our McDonalds had a play table with legos & gear style building pieces. He & the other kids would put together elaborate sculptures & then they would turn one wheel which was connected to all the others & soon the whole thing had dozens of spinning wheels going at once. It was awesome! Sometimes us parents would jump in on the fun.

Bicycles work by one wheel turning the other one as well. This time a chain is used to connect the two. The larger wheel is connected to the pedals & then the chain connects the larger wheel to the smaller one on the front.

If you have a bicycle turn it upside down. Push the pedal slowly around with your hand. Watch the two wheels...one spins faster than the other, which one? The smaller one does. The larger wheel is connected to it making it move...it supplies the force. The speed of your bicycle is determined by how fast the front little wheel spins...the back wheel pushes the bicycle forward.

Can you find other wheels, axles, & gears around your home? How about an old egg beater (turned by hand), the inside of a watch (gears), a wagon, & a pencil sharpener (turned by hand). Remember to add photos to your chart & add any other items that you think of.

Simple Machines: Screws

We haven't worked to much on school work since it is summer after all, but we did get in some work this week & did some extra work on our Machine Chart for simple machines. The last column we worked on was for Wedges, so this week we continued with Screws.

Screws are a special kind of inclined plane...really, you say? Yes, the threads of the screw go around & around on an incline. Because of these threads, a screw will hold items more firmly than a nail. Try this experiment to see for yourself:

Place a thin piece of wood on top of a thicker piece of wood, then using a hammer, nail the two pieces together. Take two more similar pieces of wood & screw them together with a wood screw. Now try to pull the two pieces apart. You'll find that the screwed pieces are harder to pull apart. It takes longer to screw pieces together than it is to nail, but it is worth the effort.

Screws can also lift & lower things, such as in a piano seat. Spiral staircases are a type of inclined plane called a screw. Screws can make work easier by increasing the amount of work with less force.

Some other objects with screws that you can see added to our chart are: The mason jar, lids, a vise, bolts, drills & corkscrews. Look around your home to see if you can find more examples of the screw.

Science Project: Machine Chart...Wedges

This is the continuation of the Machine Chart that we have been working on. So far we have introduced the Lever & Incline Plane...today we will be discussing the Wedge. The wedge is a special kind of incline plane. There are several things that we use on a daily basis that are considered wedges.

One example is an axe head. It has two sloping sides that meet together at a sharp point. A wedge increases force. When you use an axe head the sharp side goes into the wood & the sloping sides follow causing the wood to split...by the force you use.

Other examples of wedges are a chisel, kitchen knife, pins & needles. The wedge on all of these tools make your job easier to do. One of our early American presidents used a wedge when he split rails in his earlier life....do you know who that was? Abraham Lincoln!

Even some animals have built in wedges that God has given them to make their life easier...can you name any of them? We have one animal in our yard that sometimes tries to drill a hole in our siding...it sounds like a jack hammer! It is the woodpecker. Look in your nature books to see if you can find other animals with wedges.

For our chart we labeled the third column "Wedge". We then listed some wedges....Chisel, Axe, Knife, Needle, Bird's Beak, Nail, & Teeth. Yes, teeth! Feel your two front teeth. The edge is sharp & then the sides slope wider. The sharp edge enters the food & then the "force" of your bite splits the food into pieces.

List as many wedges as you can think of on your chart & add drawings & photos if you wish. Later this week we will be working on another simple machine...the screw. So check back for our chart information & experiment that we will be doing on that.

Science Project: Machine Chart...Inclined Planes

In case you haven't read my earlier blogs, my son went to public school part of this year but decided that he wanted to come back to homeschool. He made the all A's Honor Roll while he was there because a lot of the work he was doing he had already learned at home, so he was ahead of the other kids. When he came back home I just picked up where we had left off in our Alpha Omega curriculum, so I am trying to catch him up by doing some extra work during the summer...just enough to keep him busy without making him feel like he has no time off.


Today we continued working on a Machine chart that we had started which deals with simple machines. On our last lesson we worked on Levers, today we worked on Incline Planes. We first did an experiment where we created an incline plane by stacking 4 books on top of each other & then we placed one end of a board on them & the other end on the floor.


We then took one of his toy trucks & we were supposed to attach a spring scale to the front of it & lift it straight up in the air to measure the force it took to do so. Then you are supposed to again attach the spring scale to the front & pull it up the incline plane to the same height & again measure the force. However, we did not have a spring scale so I made him pay close attention to which was easier as he lifted with his own hand.


The lesson is that raising the load over a sloping distance is easier than lifting it straight up. The advantage of the inclined plane is that a man uses less force to do his work by increasing the distance he moves his load.


We then worked on our Machine chart, (see earlier posts on how to make your own). Last time we had worked on the column for "Levers". Today we marked the second column "Inclined Plane". He then drew an example of an inclined plane, the ramp, & then listed a steep road as another example. We then glued a photo of a roller coaster & labeled that.

Unfortunately, he spelled roller coaster wrong & I didn't see it before he went over it in marker...oh well!

Tomorrow we will do our final day of school for the week & will be discussing Wedges if you want to check back & work on your own Machine chart.

Science Project: Machine Chart...Levers

Here is the continuation of the Machine Chart that we started for Science last week. The first column is being used for Lever's. We discussed different levers that you see in daily life.....see-saws, etc. We discussed the 3 different parts to a lever: load, fulcrum & force. We also did a mini-experiment with a hammer & nail.

Have your child hammer a nail half-way into a piece of wood. Then let your child try to pull it out with their bare hands...they should not be able to do it. Then using the claw on the hammer to pull it out you can teach them about leverage. The nail is the load (the object being moved), the hammer is the force (being made by pushing down on it), & the fulcrum is where the hammer rests on the piece of wood as you pull out the nail. The hammer should always have contact with the wood as you put force on it...which makes it easier to do. Just a quick example of a lever for your kids.

If you are following along with your own chart write Lever at the top of the first column. Have your child draw a picture of a simple lever (we did the see-saw). Then list anything you see around your home that falls into the Lever category. We listed the hammer & nail, and an arm. An arm uses Lever movements...when you pick up something your elbow acts as the Fulcrum as you pick up your Load.

Then cut out any photos that show Levers & attach to your chart in the Lever column. (Seesaws, hammer & nail, rowboat with oars, arm picking up something).

As you continue your study & discover other Levers, add them to your list & add more photos until your column is full.

Join us next week as we continue our study of simple machines & add new ones to our chart.

Science Project: Study of Machines

Next week we will start our study of simple & complex machines. Today we made a chart to get ready to record our scientific observations. This is just the beginning of the chart & will be filled in as we go. So check back next week to see our progress & view the study of machines that you can do with your children.

First get a poster board in any color. Next turn it sideways and 10 cm from the top draw a line all the way across.

Next divide the board into seven sections (see photo). Our board was 28 in. across so our columns were 4in. in width. Do the whole thing in pencil first & then go over the lines in black marker.





Your finished chart should look like this. Again this is just the beginning, join us next week as we study machines & add to the chart, & use this study with your kids.