Alice Ramsey's Cross Country Drive

Buckle Up

Materials: Background information

Read the background information, select appropriate activity or activities for your class, have fun doing them.

You know, of course, about the Baseball Hall of Fame. But did you know that there is also an Automotive Hall of Fame? Well, there is, and on October 17, 1999, Nils Ivar Bohlin was inducted into it as the inventor of the three-point safety belt. Mr. Bohlin had been an aircraft engineer until he joined the Volvo car company in 1958. He was their first safety engineer, and his job was

to develop ways to make the Volvo safer. At that time, the two-point safety belt, which latched across the lap, was the only kind to be used. It had already been patented by 1907.

Soon after Nils developed the new three-point safety belt in 1959, all major automobile manufacturers were also using it in their cars. Now, the three-point safety belt is required by the federal government to be installed in all cars. (Incidentally, did you know that race drivers use a six-point safety belt?) With only a few small changes, Mr. Bohlin's safety belt remains almost exactly as he designed it 40 years ago. Basically, only adjustments for greater comfort have been made. Actually, the idea of a safety belt is not a new one. It is said that thousands of years ago, Odysseus, bound himself to the rudder of his ship to secure himself when he encountered storms on the turbulent seas on his trip home from Troy.

Early motorists were known to have strapped themselves into their "horseless carriages" so that they would not fall out. So Mr. Bohlin's idea is not new, but it is certainly an improvement. The fact that his invention has saved hundreds of thousands of lives makes him very happy. He says, "Sometimes I get a call from some grateful person who has survived thanks to the belt. It warms my heart and shows that I really have been able to do something for mankind."

Nils Ivar Bohlin is not the only inventor who gained fame by improving on an already existing invention. Thomas Edison, George Eastman, Henry Ford, and many other inventors did the same. One of Edison's first contributions to the world of inventions was his continuous improvement of the telegraph, an invention already in existence. Eastman improved the camera and film, both of which also had already been invented, and Henry Ford continually improved the automobile engine until it did what he wanted it to do.

Fortunately for us, automotive engineers are still seeking to improve the safety and performance of the automobile. The 1999 Mercedes-Benz S Class, the car Sue Mead and Tara Mello drove on their 1999 trip, was filled with all sorts of new safety devices. One such device is the "smart passenger" airbag. If the car hits head-on with something at a low speed, the airbag will not open with as much force as if it were traveling at a higher speed. It also has new head-protection curtain airbags on the sides of the car, and door-mounted airbags for all the doors. With such devices, the head, the chest, and the hip areas are all protected. Also on board will be the GPS Navigation System. This satellite-based navigation system uses fiber optics so that it can even respond to voice commands. Such a system can do more than find a place to stop for a good hamburger. It is a real safety feature. The state-of-the-art TeleAid system has an SOS button which gets local police, fire, or other emergency services to the vehicle quickly. How do they know where to find the vehicle in trouble? The system sends an exact description automatically to the emergency rescue service. Pretty cool, eh? It is impressive to see how much innovative effort is put into the safety of the modern transportation vehicle. Henry Ford would have loved it!

1. Research information about Henry Ford, Thomas Edison, George Eastman, and/or other inventors. Find out how they improved on already existing inventions. Prepare a written or oral report and present it to your class.

2. Make an invention of your own using a collection of odds and ends you find around the house. Name it. Write a persuasive paragraph about it. Then, create a commercial about it and try to "sell" it to your classmates.

3. Select some modern convenience, such as the common toaster, and try to think of ways in which you could improve upon it. (For example, someone fairly recently improved upon it so that it could toast a bagel.) BE SURE THAT YOUR NEW, IMPROVED VERSION HAS SOME SAFETY FEATURE! Name your new device, and present it to your classmates in one or more of the following ways:

Old Gizmo         How The Gizmos Are Alike         New Gizmo

Fill 'Er Up, Please

Materials: Background Information, Internet Access, Suggested activity list

Read the background information. Then use the internet to access information about the Shell SmartPump. Select one or more of the activities for students to do.

Have you ever watched anyone pump gas in really cold, windy, snowy, or rainy weather and thought, "Hmm! There must be a better way..."? Well, there is now a better way, and Sue Mead and Tara Mello made use of it as they traveled cross-country in 1999. It is a state-of-the-art gas pump robot. Shell Oil developed a new automatic refueling device called the SmartPump, which pumps your gas for you. To find out more about the SmartPump, read this article.

1. Read the article and consider:

2. Have a classroom debate about the SmartPump. One team supports the argument: the SmartPump is a beneficial device; the other team supports the argument: the SmartPump is not a beneficial device. Use the suggested debate form below.

3. Research the word, Robotics, and find out how many places robots are used in our lives today. You might be surprised at what you find. (Hint: try the following website: http://www.madsci.org/ Then hit Search Engine and type in Robotics.)

4. If you could build a robot which would make the world a better, safer place in which to live, what could it do? Name it. Present your idea to your classmates in one or more of the following ways:

                     *for even a greater challenge, count the number of faces, edges, and vertices you have used.

Good luck! And have fun!

Coast To Coasters, Start Your Engines

Objective: To learn about a variety of kinds of engines: water, gravity, steam, electric, and gasoline.

Read Background material for each section and select appropriate activities to do with your class. Have fun doing them!

An engine is a machine, which changes one form of energy into another, and in the process, produces mechanical work. There are all sorts of different kinds of engines. For our purposes we shall discuss engines powered by water, gravity, steam, electric, and gasoline.

I. Water Powered Engines: From early times, man has made use of the weight of falling water to do work. We are familiar with water at work as it turns a water wheel. The traditional water wheel was attached to a set of gears, and the gears were attached to grinding stones. Such a machine was used for centuries to separate grain from the shaft, and then to grind the grain. Water wheels, which used the force the motion of water flowing beneath it, were often attached to boats, setting them in motion.

Activity: Make a model of a water wheel.

Provide students with the following incomplete lab sheet. Allow them to hypothesize (selecting ..."can or cannot"...) , then create their own experiment, write their own procedure (having added to the materials list if necessary), make their own observations recording what they see, draw their own diagram, and reach their own conclusions. (Since the experiment with the water wheel and the gravity machine is similar, a good idea might be to do the water wheel experiment together, then allow students to set up their own experiment for the gravity machine using the water wheel experiment as their

model.)

Hypothesis: Falling water can/cannot produce enough energy to turn a simple wheel.

Materials: a pinwheel on a stick, a faucet with running water

Procedure:

Diagram:

Observations:

Conclusions:

Extensions:

1. How can you make the wheel turn more quickly producing more power?

2. How could you make an attachment to your water wheel to make it do work? What kind of work could it do? Make a labeled diagram of your idea.

II. Gravity Powered Engines: Gravity is the invisible force which keeps us on earth. (Actually, the weight of falling water has to do with gravity.) A gravity engine uses stored energy, or potential energy. If an object, such as a heavy stone, is held or pulled up high by some device, such as a rope, then let go, a tremendous force is released. That force can be directed to do work. For example, if a stone were held up high by a rope or by a human, then let go, it could drive a stick into the ground. An engine called the "pile driver" uses this kind of energy. A pile driver is used in construction to drive large spikes into the ground often to build foundations. The engine consists of a very heavy hammer-like device which can slide up and down on a track. It utilizes some sort of energy to pull it up the track. Then it drops the hammer-like device, potential energy is released, the hammer falls, and work of some sort is done.

Activity: Build a model of a sand engine.

Provide students with the following incomplete lab sheet. Allow them to hypothesize (selecting ..."can or cannot"...), then create their own experiment, write their own procedure (having added to the materials list if necessary), make their own observations recording what they see, draw their own diagram, and reach their own conclusions.

Hypothesis: Falling sand can/cannot produce enough energy to turn a simple wheel.

Materials: a funnel, sand, a pinwheel on a stick, a bucket to catch the falling sand

Procedure:

Diagram:

Observations:

Conclusions:

Extensions:

1. How can you make the wheel turn more quickly producing more power?

2. How could you make an attachment to your sand machine to make it do work? What kind of work could it do? Make a labeled diagram of your idea.

III. Steam Powered Engines: Both kinds of power we have discussed this far have depended on the natural forces of nature. The following three kinds of engines require more human intervention. In order for a steam engine to work, it needs to have a practical and reliable source of steam. Since steam comes from boiling water, in order to produce a steam engine, one must provide both a container for the water, and a source of energy to heat it to boiling.

1. Take a tea kettle, fill it with water, heat it to boiling, and place a pinwheel in the path of the steam. The pinwheel will turn. This very simplistically, is how a steam engine works!

2. Make a Steam Boat.

This experiment is probably best demonstrated by the teacher as it involves fire. Students, however, having seen the demonstration could write up their own lab sheet using the models from the previous experiments.

Hypothesis: The power of steam can produce enough energy to move a small steam boat.

Materials: 3 votive candles, 1 small metal dish, 1 small metal tube which has a lid (a cigar tube works well), 1 large pan of water in which the "boat" can float (a large baking pan works, though a larger the container makes for a more dramatic demonstration), a small ball of modeling clay, boiled water, matches

Procedure: Fill the large pan with water. In the small metal dish, place three votive candles. Fill the metal tube about ¾ full of already boiling water. Cap the cigar tube, having poked a small hole in the cap. Use modeling clay to keep the tube in place, put the tube across the small metal dish. Light the candles. Place your "steam boat" in the larger pan. See what happens.

Observations: (the boat should move!)

Conclusions: (Steam can provide enough energy to power to do work)

A steam engine is really just a sophisticated and efficient "tea kettle." When a great deal of pressure is created, steam will be produced. In order for a steam engine to work, that pressurized steam exits the boiler through a pipe, past a valve, and then into a cylinder, which is really just another pipe, closed at one end and open at the other. Inside the pipe, (the cylinder), there is a disk which is called a piston. It can slide up and down the cylinder. It has a rod of some sort attached to it. As the steam is pushed into the cylinder, it pushes against the piston. The piston then is forced down into the other end of the cylinder. That comprises one "push". Many continuous "pushes" are required for a steam engine to work. See the diagram below, which shows that the rod is connected to a flywheel. As the piston moves up and down, the rod moves back and forth, and the wheel turns. The wheels of locomotive use such an engine to make them turn.

IV. Electric Powered Engines: Electric motors are found everywhere! They come in different sizes, from huge ones which power submarines or locomotives, to tiny ones found in tiny electric clocks. Electricity is not the easiest concept to understand, as it cannot be seen. It works by pushing tiny invisible particles, called electrons, through copper wire. In order for moving electrons to produce power, they have to flow continuously. As soon as the flow of electrons is cut off, there is no electricity (electric current). When an electric current flows from a battery or some sort of generator, through wires and back again over and over, it has created a complete circuit. Only then is energy released to do work.

Make a small electric motor. You will need the following materials:

Make a neat circular coil by making 30 turns of wire around the broom handle. Remove the broom handle, and flatten the coil using small pieces of tape to keep the coil in a circular shape. Leave 3 to 4 inches of the coil ends free. The wound bundle of coil becomes the armature. Take the steel knitting needle and pass it right through the wires of the coil itself, on through the opposite ends of the coil to the crossed nail, where it should rest. Scrape away the insulation for about 2 inches, from the tips of the coiled wire. Those bare wires are called commutator contacts (#1 and #2), and, again, the coil itself is called the armature. Someplace near the center of the steel needle, insulate it with a few inches of tape. Attach the bared ends of the coiled wire to the spindle with tape. Suspend the spindle (the thin, steel, knitting needle) with its armature and commutator, between two pairs of crossed nails, over a block of wood. Place a strong bar magnet just under the coil making sure it will not be in the way of the coil as it spins. Take the bare ends of two other, separate, copper wires and connect them to a 4.5 volt battery. Scrape about 2 inches of insulation from those wire ends. Those then become brushes. Touch the brushes to commutator contacts #1 and #2. The motor should start by itself and keep spinning. The armature has become an electromagnet. See the diagram below.

Extensions:

1. Experiment using the Scientific Method to find out:

2. How could you connect this small electric motor to a device which could do work? What kind of work could this do?

3. Do you think this kind of motor is practical for use in an automobile engine?

V. Gasoline Engines: The remains of tiny little plants and animals buried deep into the soil of the earth hundreds of millions of years ago has resulted in the creation of one of the most commonly used fuels on earth. Having been buried so long and having been subjected to such enormous pressure, those organic remains eventually underwent chemical changes. The result was the formation of an incredible source of energy, the fuel we know as oil, or petroleum. Today, petroleum is pumped out from deep in the earth's crust, is treated in such a way that impurities are removed, and becomes what we know as gasoline. There is such enormous energy stored in the molecules of gasoline, that a mere spark from a fire sets it off with a giant explosion. Gasoline is the fuel most vehicles use today, though many alternate sources of fuel are now being sought. The earth's reserves of petroleum are becoming limited, and could, conceivably even eventually run out. Air pollution is also a problem when gasoline is burned as a fuel. We must find other ways to power our vehicles.

Since the use of the gasoline engine is so common, we should know something about how it works. In a gasoline motor, the gas goes from the gas tank to the carburetor. There it gets mixed with air making the gasoline even more explosive. The explosion caused by this addition of air takes place inside a cylinder. There, it is touched off by an electric spark caused by a "spark plug." An explosion is the result, and enormous pressure is created as the gases burn. The energy caused by that heat is called "thermal energy." Thermal energy causes the gas to expand causing great pressure, and that pressure pushes down the piston. Thus, thermal energy is converted to "mechanical energy." You will remember that a steam engine also makes use of a cylinder in which the piston moves in an up and down motion. There is an important difference, however, as to where the burning takes place. In the steam engine, the burning takes place outside the cylinder, while in the gasoline engine, the burning (combustion) takes place inside the cylinder. That is why the steam engine is called an external combustion engine, and the gasoline engine is called an internal combustion engine.

The sequence of the action of the gas through the cylinder takes place in four basic strokes. In the first stroke, the piston moves up and down as the mixture of air and gasoline comes from the carburetor through the intake valve. This is called the Intake Stroke. Then both valves close, the fuel and air compress, and the piston moves up. This is called the Compression Stroke. The third stroke is caused when the spark plug ignites the mixture forming very hot, expanding gases. The piston pushes down with great force and power is produced by the engine. It makes sense, then, to call this the Power Stroke. Finally, in the fourth stroke, the piston goes up again. The exhaust valve is opened, and the gases are pushed out of the cylinder. The gases are still very hot. This final stroke is called the Exhaust Stroke. The engine is then ready to begin the whole four-part cycle again. Though the process sounds rather simple, the timing of each step has to be perfect, or the motor will not work. Many gears and levers are needed to make the timing and sequences exact. It is truly very complicated, as the valves must move open and closed at exactly the right moment, and the spark plugs must ignite at precisely the right time. And if that weren't enough, this is all happening at an incredibly rapid rate; literally thousands of explosions per minute take place. The result is the back and forth motion of the piston, called "reciprocating motion." The pistons are connected to the connecting rod, which is connected to the crankshaft, which is in turn connected to the flywheel. At that point, reciprocating motion is turned into "rotary motion," which eventually allows the wheels of the car to turn. And, with this very simplistic explanation of the gasoline engine, off you go!

Using the information written about the gasoline engine, see how well you can answer the following questions:

MATCHING

A. carburetor

B. fuel tank

C. cylinder

D. spark plug

E. external combustion engine

F. piston

G. internal combustion engine

H. intake stroke

I. thermal energy

J. mechanical energy

K. reciprocating motion

L. connecting rod

N. crankshaft

L. connecting rod

N. crankshaft

O. rotary motion

P. Power Stroke

 

___1. Connects the connecting rods to the fly wheel

___2. The kind of energy produced by heat

___3. Place where explosion takes place in an engine

___4. Gas comes from carburetor in this stroke

___5. Engine in which "explosion" takes place inside cylinder

___6. Place where air mixes with gasoline

___7. Part of gas engine that moves up and down in cylinder

___8. Sets off a spark which ignites air/gasoline mixture

___9. The only stroke in which power is produced in the engine

___10. Place in car where gasoline is stored when car is not in use

___11. The kind of energy which causes work to be produced

___12. Connects pistons to crankshaft

___13. Engine in which "explosion" takes place outside cylinder

___14. The kind of motion which pistons make as they go up and down

___15. The kind of motion which eventually allows the wheels to turn

 

KEY:

1-M, 2-I, 3-C, 4-H, 5-G, 6-A, 7-F, 8-D, 9-P, 10-B, 11-J, 12-L, 13-E, 14-K, 15-

O

 

TRUE OR FALSE:

___1. Fossil Fuels Were Once Living Plants And Animals

___2. Petroleum Is A Fossil Fuel.

___3. Cars Use Petroleum As Fuel Exactly Is It Comes From The Earth

___4. Gasoline Is Less Explosive When It Mixes With Air.

___5. When Gases Leave The Cylinder Through The Exhaust Valve, They Are Still Very Hot.

___6. Many Gears, Levers, Etc, Are Necessary To Get The "Timing" Just Right In A Gasoline Engine.

___7. As Gases Expand, They Create Enormous Heat

___8. Thousands Of "Explosions" Occur In One Minute Inside The Cylinder Of Gasoline Engines.

___9. It Is Not Necessary For The Explosions In The Cylinder To Be Timed Exactly Right.

___10. As Gases Get Hot, They Expand.

 

KEY:

1. T 2. T 3. F 4. F 5. T 6. T 7. T 8. T 9. F 10. T

 

ANSWER THESE IN WELL WRITTEN PARAGRAPHS