SIMPLE PHYSICS PROJECT

1. Senter Sederhana Bertenaga KOIN (4 person)
2. Rem Hidrolik (3 person)
3. Alat Pengukur Kesuburan Tanah Sementara (3 person)
4. Pemotong Gabus Sederhana (4)
5. Alat Penetas Telur Sederhana (3)
6. Vacuum Cleaner Portable (2)
7. Teropong Sederhana (4)
8. Lup Sederhana (3)
9. Alat Pendingin Sederhana (4)
10. LED portable (4)
11. Alat Pemanas Sederhana (4)
12. Lampu Nokturnal (4)
13. Penguat Sinyal Modem Sederhana (4)
14. Kompor Listrik Sederhana (4)
15. Bel Listrik Sederhana (3)
16. Mesin Atwood Sederhana (3)
17. Alat Penghasil Listrik Tenaga Hamster (5)
18. Charger Portable (4)
19. Replika Lift Tenaga UAP (4)
20. Pembangkit Listrik Tenaga Angin (4)
21. Robot Hidrolik (4)
22. Pompa Listrik (4)

UNTUK PANDUAN PEMBUATAN ALAT-ALAT PERCOBAAN FISIKA SEDERHANA DIATAS. SILAHKAN MENGHUBUNGI PAK RIFQI  (for further information about the required materials and the procedures, please call Pak Rifqi, but before doing experiment, please call Mr Oktem for registration the group and the Project you are interested in)


Source: Laboratorium Fisika Dasar, UIN Syarif Hidayatullah Jakarta (UIN Syarif Hidayatullah Jakarta Physics Laboratory)

Build an Electromagnet

Purpose

To find out how electromagnetism works by constructing an electromagnet and be able to answer the question “How does electromagnetism work?”

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Additional information

Do you ever wonder how the telephone, electric bell, and electric motors that run most of our appliances at home work? Electricity can be transformed into energy of motion or mechanical energy and it is all because of the discovery made by Professor Hans Christian Oersted in 1820. Professor Oersted is a physics professor who discovered that a wire carrying electric current generated a magnetic field. He referred to this phenomenon as electromagnetism. An electromagnet operates only when there is a flow of electricity in the coil of the wire. Its magnetism can be turned on and off at will. It is made up of an iron core, wire, and source of electrical energy.

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Sponsored Links

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Required materials

• half meter copper wire
• one dry cell
• 1iron nail about four centimeters in length
• electrical tape
• iron filings

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Estimated Experiment Time

About fifteen minutes

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Step-By-Step Procedure

• 1. Get a half meter long copper wire and remove the insulation at both ends.
• 2. Wound the wire around the nail.
• 3. Attach the ends of the poles to the dry cell.
• 4. Trace the path of electricity in this device.
• 5. Bring the nail near some iron filings.
• 6. Observe how the iron filings behave.
• 7. Predict what would happen if the wire was detached from the dry cell.
• 8. Detach one wire from one terminal of the dry cell.
• 9. Observe what happens.

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Note

Be careful in removing the insulation of the copper wire to make sure you don’t damage it. Nails and ion filings are sharp so do not play with them. Wound the wire tightly and securely around the nail for positive results.

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Observation

When you attached the ends of the wires to the poles of the dry cell, was the circuit close or open? What happened when you brought the nail near some iron filings? What happened to the iron filings when you detached one wire from one terminal of the dry cell? What property is exhibited by the nail when electricity flows along its wire?

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Result

The circuit was closed when you attached the ends of the wires to the poles of the dry cell. When you brought the nail near the iron filings, they reacted to the nail as shown by their movements. After detaching one of the wires from the dry cell, the iron filings no longer showed any reaction to the nail. The nail in this experiment acted like a magnet. Electricity flowing in a conductor like the nail produces a magnetic field which results to magnetism. The nail attracts magnetic objects like the iron filings. The strength of an electromagnet is influenced by the number of turns it has on its coil, the material used and the amount of electricity in the wire. Electromagnets are found inside the telephone, washing machine, and many others.

Information and CD's

 Information and CD's

 

Purpose

To find out how much information is stored on a compact disc without using a computer.

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Additional information

You will need to become familiar with what a burned CD looks like – look at one under a light and you will see where the “burned tracks” start (at the center of the disc) and where they stop. This is the information that you will be measuring.

Required materials

• Computer capable of burning CD’s
• 8 unused CD-R discs
• Any file that is roughly 100 MB in size
• Ruler
• Marker for labeling the used discs
• Journal or logbook

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Estimated Experiment Time

A few hours

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Step-By-Step Procedure

• 1. Set up two identical copies of your 100 MB file. One will be used as your “control,” so it is a good idea to save it somewhere out of sight for now. The second copy of the file will be used for burning. Name each copy of the file.
• 2. Create a table within your journal or logbook to record the data. For each disc that is burned, you should record the unused data on the disc, the used data on the disc and the distance from the center that the “burned tracks” stop.
• 3. Burn the file on the first disc. Record the unused data and the used data for each disc into your journal or logbook and measure with your ruler the distance from the center of the disc to the end of the “burned tracks.” Record in your journal.
• 4. For the second disc, add another copy of the same file. Burn that disc and record the information. For the third disc, add yet another copy of the same file – on disc three, there should be three copies of the same file. Each time you burn a disc, you will add another copy of the file.
• 5. Label each disc with a number or appropriate name so you will be able to tell the difference between the different discs.
• 6. When you are finished, graph the results.

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Note

You may need an adult to help you burn information on the CD’s as well as show you where to find the used disc space and the unused disc space.

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Observation

The hypothesis is that the unused space will diminish as more files are burned onto each disc.

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Result

At the end of the project, you should be able to estimate the amount of space used on each disc solely by the measurement from the center of the CD to the end of the “burned tracks.”

Gravity and Plants

Gravity and Plants

Purpose

NASA has long studied the effects of gravity on plants by taking plants with them during space expeditions and onto space stations. You can find out for yourself how plants grow in low gravity conditions by conducting this simple experiment.

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Additional information

When plants are upright, they are growing directly against gravity. Since most plants grow in this manner, you can be sure that plants thrive by fighting against gravity. What would happen if plants were to be placed on their sides, where if they were to continue on their current path of growth, they would not be growing directly against gravity but rather, partly with it?

Required materials

• 3 bean plants or seeds
• 3 peat pellets (if using seeds only)
• 3 small to medium sized pots
• 1 medium bag potting soil
• 2 gallons distilled water
• Ruler
• Protractor
• Area in your home where the plants can reside for several weeks without being disturbed
• Journal or notebook paper
• Camera (if available)

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Estimated Experiment Time

Several weeks.

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Step-By-Step Procedure

• 1. Prepare bean plants by placing each plant or seed in one of your pots that have been filled with soil. If you are using a bean plant, you will need to plant it at about mid-depth within the pot. Seeds need to be sprouted in peat pellets before placing in pots if you are using seeds.
• 2. Once bean plants have been prepared, allow them to grow for a few weeks. Take photos if possible and record the plants’ growth in your journal or logbook.
• 3. Once the bean plants have reached about four or five inches high, turn the plants on their sides. This will create a “low gravity” condition.
• 4. Continue to allow the plants to grow, documenting their growth.

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Note

You may want to consider mapping out your plants’ growth after the completion of the experiment by creating a growth chart. This will visually represent your findings.

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Observation

Taking photographs if you can and documenting each measurement in your journal is a very important step in this project and must not be left out. These will truly illustrate your project to onlookers, helping them to understand the information you’re presenting.

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Result

Scientists and technicians have found that plants will grow directly against gravity, no matter which way they are facing. Did your plants start to grow upwards again once they were placed sideways? Did placing them sideways cause them to change direction? What do you think happens to plants in low gravity conditions such as those on a space shuttle or space station?

source: http://www.sciencefairadventure.com

Spectrum Through Water

Spectrum Through Water

Purpose

To create a spectrum using a beam of light passing through water

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Additional information

A glass simple prism can be used to split a beam of white light into its component colors. The phenomenon due to which white light splits into component colors is called dispersion.

Required materials

• Shallow bowl
• Water
• Mirror
• Torch

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Estimated Experiment Time

Less than 5 minutes

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Step-By-Step Procedure

• 1. Fill a shallow bowl with water
• 2. Place a mirror in this shallow bowl containing water so that it is at an angle of about 30 degrees to the surface of the water
• 3. Make the room dark (switch off lights / cover windows with dark cloth or paper)
• 4. Shine the torch on the mirror

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Note

The angle at which the mirror is placed is crucial to the formation of the spectrum on the ceiling.

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Observation

When a beam of light from the torch is shone on the mirror immersed in water, a small spectrum of rainbow colors appears on the ceiling.

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Result

The experiment proves that white light is composed of different colors of the spectrum, each possessing different wave lengths. Each water molecule acts as a simple prism causing the refraction of each wave length of light at a different angles ultimately leading to the formation of the colors of the spectrum on the surface on which the reflected beam of light falls.

Vibrating Coin

Vibrating Coin

Required materials

• Coin
• Bottle
• Refrigerator
• Water

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Estimated Experiment Time

Approximately 15 to 20 minutes

Purpose

To demonstrate the expansion of air when heated.

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Additional information

The temperature of a gas is directly proportional to the speed with which its molecules move. Increasing the temperature of a gas results in an increase of the average speed (and therefore the kinetic energy) of its molecules. This in turn causes the molecules to ‘spread out’ by virtue of a phenomenon 

Step-By-Step Procedure

• 1. Place an empty bottle in a refrigerator to cool
• 2. Place the cooled bottle outside
• 3. Dip your finger in water and place a few drops around mouth of the bottle and the edge of the coin
• 4. Place a coin on the mouth of the bottle
• 5. Place both your hands around the bottle; hold firmly
• 6. Remove your hands after a while

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Note

• Use a bottle with a mouth narrow enough to be closed completely with a coin.
• Applying water on the rim of the bottle mouth and the coin’s edge will help seal the bottle.

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Observation

In approximately fifteen seconds from covering the bottle with your hands, the coin will start to vibrate up and down. When you do remove your hands after a short while, the coin continues to vibrate.

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Result

As soon as the bottle is taken out of the refrigerator the temperature of the gas inside the bottle begins to rise; encasing the bottle with your hands increases the temperature further. When the bottle is heated, the air molecules inside it start moving faster and these molecules collide with the coin with more energy. This results in increased pressure which in turn is caused by the expanding air that escapes though the rim of the coin and makes it vibrate.

source: http://www.sciencefairadventure.com

Make an Elevator

Make an Elevator

Purpose

To demonstrate how elevators work through a series of pulleys by constructing our own elevator system.

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Additional information

Elevators are vertical lift transportation systems that effectively move people between floors of buildings. Most are powered by eclectic motors that pull steel cables along pulleys.

The first known reference to an elevator comes from the Roman architect Vitruvius. He reported that mathematician and inventor Archimedes built the first elevator in 236 B.C. Elevators in this time period were mentioned to have been constructed from hemp rope and powered by hand or animals. Prototypes of elevators were later found in palaces of both England and France.

By the middle of the 1800's, there were dozens of crude elevators that were designed to carry both freight and human. These ancient elevators worked through hydraulic systems, the first every using a plunger below the elevator car to raise or lower it. To assist in lifting the enormous weight of the elevator, a counter-balancing system was implemented.

Required materials

• Piece of plywood (or other suitable hard surface wood)
• Six empty spindles
• A cardboard box (we'll use this to create our small elevator)
• String or thread
• Six nails
• A small weight, such as a heavy screw
• Tape
• Scissors
• Ruler
• Pen or Pencil
• Hammer

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Estimated Experiment Time

Between 1 and 2 hours

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Step-By-Step Procedure

• 1. First we'll need to construct our tiny elevator car from the cardboard box. Using your ruler and pen, draw five six-inch by six-inch squares on your cardboard box. Cut the squares from the box with your scissors. Tape the squares in a manner that will make an open box. Do this by aligning the squares at their edges and joining them together with some tape. Once complete your elevator should look like the example in Figure A.
• 2. Attach the spindles to the wooden frame using the nails. The spindles should be aligned so that four are spread evenly at the top of the wood, about four inches apart for each spindle. Two additional spindles should be placed at the bottom of the box, also four inches apart. See Figure B as a placement guideline.
• 3. Tie a piece of string to the bottom of your cardboard elevator car. Tie two additional strings to the top of your elevator car. See Figure A for an example.
• 4. Pass the string attached to the bottom of the elevator car over the spindles 4, 3, 2, and 1. When you get to spindle 2, loop the string over the spindle twice. Tie the end of string to the string on the top of the box once it loops over spindle 1 (see Figure B).
• 5. Attach the other string on the top of the elevator car around spindles 5 and 6. Make sure the string lays over the spindles tightly and attach your counterweight (a large nut, screw, heavy key, or any other weight that's appropriate).
• 6. Make sure all strings are tight and all spindles are firmly in place.
• 7. Turn the second spindle with your fingers (labeled 2 in the Figure B). What happens to the elevator car? If constructed correctly, the elevator car should move up or down, depending on the direction you rotate the spindle.

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Note

Positioning the spindles and getting them to stay on your wood piece may be tricky at first, but keep trying! The positioning doesn't have to be perfect. You just want to make sure that the spindles are positioned in a way that the string will be able to sit atop them snugly, while still allowing them to rotate. It may take several tries before you get everything just right. 

Observation

What happens when you turn the spindle? Does your elevator car move up? Does it move down? How do you think the counterweight affects the movement of the elevator car? What do you think would happen if you added some weight (to mimic people) inside the elevator car?

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Result

When you turn spindle 2, the string attached is wound or unwound, resulting in the elevator car moving up or down. The counterweight is used to balance the weight of the elevator car so it's easier to pull up. As the elevator is lifted up, the counterweight moves down.

Make a Fuse Model

Purpose

To make a model of a fuse. After this experiment, you will realize the importance of the fuse and be able to answer the question, “How can a fuse help prevent fire caused by faulty electrical wiring?”

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Additional information

Many devastating fires have been caused by faulty electrical wiring. An overloaded circuit or short circuit can cause fire. Sometimes, there are many devices connected to the outlet. The current drawn by the outlet increases and produces heat that causes the wire to become hot. The hot wiring may ignite the materials surrounding it and start a fire. To prevent fires caused by faulty electrical wiring or devices, fuses are installed in homes, offices, and other infrastructures. A fuse is found in a fuse box. The electric current from the power line fuses to the electric meter and then to the fuse box and so to the establishment wires. A fuse contains a thin piece of metal. When the circuit becomes overloaded, the metal strip melts and destroys the fuse. The current will no longer flow through the circuit unless the burnt fuse is replaced. A short circuit may occur when bare wires come into contact and more current moves in the circuit. It can be caused by damaged or worn out electrical wiring. Sometimes, small animals like rats and rodents chew off parts of the insulation.

Required materials

• two dry cells
• flashlight bulb with socket
• two thumbtacks
• two metal paper clips
• 13 x 18 cm wooden block
• 3cm aluminum foil
• half a meter copper wire cut into four
• screw driver
• electrical tape
• scissors

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Estimated Experiment Time

Around 30 minutes

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Step-By-Step Procedure

• 1. Get two paper clips and tack them on one side of the wooden block.
• 2. Insert the strip of aluminum foil between the paper clips (this acts as the fuse).
• 3. Connect the dry cells by taping one wire to the positive side of the first cell and the other end attached to the negative side of the second cell.
• 4. Get another wire, remove a part of the insulation in the middle, and tape the end on the positive side of the second cell.
• 5. Then attach the other end to the left thumbtack on the wooden block.
• 6. Attach another wire to the negative side of the first dry cell and connect it to the left side of the light bulb.
• 7. Remove a part of the insulation in the middle wire and attach the end to the right side of the light bulb.
• 8. Then wound the other end to the right thumbtack on the wooden block.

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Note

Remove the insulation slowly to avoid damaging the wires. Do not play with the thumbtacks to avoid being pricked.

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Observation

Did the bulb light up? What happens when you place a screw driver across the bare wires? What happens to the aluminum foil?

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Result

Placing a screw driver across the bare wires caused a short circuit because the aluminum which serves as the fuse heats up and breaks the circuit. Safety devices like the fuse can help prevent uncontrolled fires caused by faulty electrical wiring.

Jar Compass

Jar Compass

Purpose

To demonstrate the earth's magnetic force by creating our very own compass in a jar.

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Additional information

A compass is an instrument used for navigation relative to the earths magnetic poles. It's magnetized pointer aligns itself to the earths magnetic field to calculate heading, allowing for safer and more efficient maritime travel. Compasses are often built as stand alone instruments, sealed with a magnetized bar and freely turning needle upon a pivot. Most compasses highlight the four cardinal directions or cardinal points of north, south, east, and west.

Required materials

• Needle
• Magnet
• Scissors
• Small piece of card
• Jar
• Thread
• Pencil
• Compass

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Estimated Experiment Time

Approximately 15 to 20 minutes

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Step-By-Step Procedure

• 1. Stroke the needle with the magnet several times to give it a magnetic charge.
• 2. Tie one end of the thread to the small piece of card and the other to the center of the pencil. Tying the thread to the card can be tricky, but carefully poke a small whole into the top end of the card that's just wide enough to run the thread through. Loop it around the card and tie in a knot.
• 3. Push the needle through the center of the card, stop when the needle is dead-center in the middle of the card.
• 4. Suspend the piece of card inside the jar by laying the pencil across the mouth of the jar so the card is dangling in the center of the jar. Do not allow the card to hit the bottom of the jar!
• 5. The needle should lie horizontally. Make sure to get the middle of the needle to rest in the middle of the card.
• 6. Place the jar on a flat surface next to your compass and leave it to stand freely. The needle in the jar should point in the same direction as your compass.

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Note

Setting up the jar compass can be tricky the first time. You can refer to the following figure to get a general idea on how your compass should be set-up.

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Observation

What happens when you turn your compass and your jar in another direction? Does the needle in your jar point in the same direction as your compass?

If your needle doesn't seem to be spinning with your compass, you may need to re-magnetize it.

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Result

The magnetized needle is free to turn on its own and will always point north and south. The needle is acting as a magnet and is attracted to the earth’s magnetic force.

Galileo's Experiment

Galileo's Experiment

Purpose

To demonstrate Galileo's falling objects experiment that states "What goes up, must come down". After this experiment you'll be able answer the question "Do larger objects fall faster than lighter ones under the same conditions?"

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Additional information

Born in 1564, Galileo Galilei was an Italian physicist, astronomer, philosopher, and mathematician. Around the year 1589 Galileo set out to prove that two objects of varying size and weight would hit the ground at the same time when dropped from great heights. This was contrary to popular belief and the teachings of Aristotle, who theorized that objects of greater weight fall faster than those of lighter weight. To prove his theory, it's said that Gelileo dropped a 10 pound ball and a 1 pound ball from the top of the Leaning Tower of Pisa. A large crowd witnesses Galileo prove his theory and disprove Aristotle’s when the balls hit the ground at the same time.

Required materials

• two balls of the same size, but different weights (preferably steel balls or balls not made out of rubber)
• a ladder (or an area of significant height where the balls can be dropped safely)
• a notepad to record observations.
• a video camera to record results (optional, but recommended)
• a video camera tripod (optional)

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Estimated Experiment Time

About 10 minutes for multiple samplings

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Step-By-Step Procedure

• 1. If using a video camera, set the camera up on a tripod or solid surface. Make sure to position the camera so that it can capture the entire procedure (from the point the balls drop to where they hit the ground).
• 2. Climb the ladder and prepare to drop both balls at the same time. It's best to have someone spot you and help you balance while on the ladder.
• 3. Once situated safely on the ladder, place a ball in each hand. Hold both hands out at equal length and distance.
• 4. Count to 3 and release the balls at the same exact time.
• 5. After the balls hit the ground, record the results in your notepad.
• 6. To verify your notes, review the optional video recording.
• 7. Repeat the experiment several times, preferably a minimum of 10 times. Record the results separately for each iteration of the experiment.

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Note

To avoid injury, ensure everyone is clear from the area where you'll be dropping the objects, especially heavy objects. Also ensure that you have someone to help keep your balance if conducting the experiment from the top of a ladder.

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Observation

When you dropped the balls from the ladder, which ball hit the ground first... the heavy ball or the light ball? If one hit before the other, how many times did this occur? Galileo's experiment is contingent on objects being dropped under the same conditions. With any experiment, there is a degree of human error that can result in skewed results. We conduct the experiment several times to ensure our results are accurate and to take into account variances (such as not releasing the balls at identical times). The video recording is key to ensure our testing conditions were identical and to verify results.

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Result

When dropped, both the heavier ball and the lighter ball should hit the ground at the same exact time, proving Galileo’s theory that objects, in direct proportion to weight, fall at the same rate.

Balloon Rocket Car

Balloon Rocket Car

Purpose

To demonstrate Newton's Third Law of Motion by constructing a balloon-powered rocket car.

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Additional information

Newton's Third Law of Motion (law of reciprocal actions) states: "Whenever a particle A exerts a force on another particle B, B simultaneously exerts a force on A with the same magnitude in the opposite direction. The strong form of the law further postulates that these two forces act along the same line." This law is often summed up in the very cliché saying "Every action has an equal and opposite reaction".

Required materials

• Large Styrofoam tray to construct the car body and wheels from (or any flat Styrofoam piece)
• 4 pins (to serve as wheel axels)
• Cellophane tape
• Flexi-straw
• Scissors
• Drawing compass
• Marker pen
• Small to medium party balloon
• Ruler

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Estimated Experiment Time

Approximately an hour to construct the car and conduct the experiment

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Step-By-Step Procedure

• 1. Using your ruler, drawing compass, and marker, draw a rectangle on the Styrofoam tray that's 7.5cm by 18cm. Draw an additional 4 circles at 7.5cm in diameter.
• 2. Use the scissors to cut the rectangle and 4 circles from the Styrofoam tray.
• 3. Stretch the balloon by inflating it several times and letting the air out.
• 4. Insert the balloon nozzle over the short end of the flexi-straw (nearest to the bendable section). Secure the balloon nozzle to the straw with tape. Make sure to seal it tight while ensuring the balloon can be inflated by blowing into the straw.
• 5. Tape the straw to the rectangle. To do this properly, place the straw so it's in the center of the width of the rectangle. Allow the section of the straw with the balloon attached to be raised slightly while the end without the balloon should extend about an inch or two over the rectangle (see illustration)
• 6. Push a pin into the center of the circles and then push into the Styrofoam rectangle to make four wheels. Make sure to leave some room for the wheels to spin (too tight and the wheels won't rotate).
• 7. Inflate the balloon through the straw. Pinch the straw nozzle, place the car on a flat smooth surface, and then release the straw. Weeeee!!!!!

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Note

If you're having trouble getting the wheels to stay on, you may need either a thicker piece of Styrofoam or thicker pins. Make sure when inserting the wheels you leave some of the pin sticking out so the wheels don't slide off. Also, feel free to construct cars of varying shapes and sizes to see how their affected by the experiment. Originality and creativity in car construction is encouraged!

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Observation

Make careful note of the movement of the car in relation to the balloon size. You should record your observations in a journal. Some questions that may be answered are: What happens when the balloon nozzle is released? Can you explain why and how the car is propelled across the floor? Can you explain how Newton's Third Law is being applied in this project?

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Result

When the straw is released, the car is thrust forward and propelled across the floor. This project satisfies Newton's Third Law of Motion of "Every action has an equal and opposite reaction". In this case, the air escaping through the straw (the thrust) is the action while the car's propulsion across the room in the opposite direct is the reaction.

source: http://www.sciencefairadventure.com/Physics.aspx

Wobbly Balloon

Learn about gravity and air resistance as you make a balloon wobble through the air.

You will need

• Balloons
• Marble

What to do

1. Blow up a balloon and tie the end.
2. Bounce the balloon into the air with your hand and observe how it moves.
3. Place a marble in another balloon. Blow this balloon up and tie the end.
4. Bounce this balloon into the air with your hand. How does it move?

What's happening?

The first balloon has a relatively small mass compared to its volume. The balloon falls due to gravity, while air resistance slows its fall. Another way of saying this is that the force of air resistance has an effect on its inertia. The materials making up the balloon (the air and the rubber skin) are spread fairly evenly around the middle, making the balloon fall smoothly.

The marble in the second balloon doesn’t behave like the balloon around it. It is denser, meaning the force of air resistance on its movement has less of an effect on its inertia than on the balloon’s inertia. It hits the side of the balloon and bounces back. The balloon also feels an equal force from the marble, but in the opposite direction, pushing it away from the marble.

This is a good example of Newton’s first law of motion on inertia, and third law of motion on opposing forces.

The marble keeps moving and bouncing around inside the balloon, which results in the wobbly motion of the balloon.

Applications

Air resistance is an important consideration in the design and function of aircraft. The higher up in the atmosphere, the thinner the air. This lowers the air resistance meaning planes require less fuel to achieve the same speed.

In the case of parachutes, a high air resistance is required. The large surface area of a parachute results in a large air resistance. This slows down the person so that they are able to land safely.