The document describes three simple science experiments: a balloon-powered rocket car demonstrating Newton's Third Law of Motion, a matchbox guitar demonstrating how string instruments work, and a vibrating coin experiment demonstrating the expansion of air when heated. Each experiment includes the purpose, materials, procedure, observations, and results. The balloon car experiment shows that when the air escapes the straw, the car is propelled in the opposite direction. The matchbox guitar uses rubber bands as strings to create sound by plucking. In the coin experiment, heating the bottle causes the air molecules to move faster, increasing pressure and making the coin vibrate as the expanding air escapes.

1. SIMPLE SCIENCE EXPERIMENTS
Submitted To
Miss. Jeena
Submitted From
Malu . R
Roll No. 35
MMTC VILAKUDY

2. Balloon Rocket Car
Purpose
To demonstrate Newton's Third Law of Motion by constructing
a balloon-powered rocket car.
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
Estimated Experiment Time
Approximately an hour to construct the car and conduct the experiment
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)

3.  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!!!!!
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!
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?
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.

4. Matchbox Guitar
Purpose
To demonstrate how string instruments work by building our
very own miniature guitar from a matchbox.
Additional information
Traditional guitars are played acoustically, where the sound produced is a result of the
vibration of the strings and modulated by a hollow body. Electric guitars produce an
electronically manipulated tone when played through amplifiers. As the guitar strings
are plucked, the guitar pickup senses the vibrations from the strings and sends along
an electronic signal to the amplifier. The amp reads the signal and converts it into an
adjustable audible sound by boosting it through a speaker system.
Traditionally, guitar strings were made from cat intestines. These days strings are
made from nylon, horse hair, bronze, and steel.
Required materials
 Empty matchbox
 4 small rubber bands
 Balsa wood (very soft and light wood with a coarse open grain, suitable for carving)
 Craft knife
Estimated Experiment Time
About 15 to 30 minutes
Step-By-Step Procedure
 1. Cut the piece of balsa wood into a flat triangular shape so that its length is a little
longer than the width of the matchbox.
 2. Place the triangle across the width of the matchbox so that the pointed end is
hanging over. You don't need the piece that is hanging over, so cut it off. You now have
what is called the "bridge".

5.  3. Lay the bridge on the closed matchbox. Open the matchbox so it's about three-fourths
open.
 4. Put the rubber bands over the matchbox lengthwise and space them evenly. Make
sure the rubber bands are tight. This can be done by opening the matchbox a little more.
 5. Raise your bridge so that it stands up. Play your guitar!
Note
If you're having trouble getting the bands to fit tightly around the matchbox, smaller
rubber bands may need to be used. Also, if you find your bands slipping off the bridge,
you can create small grooves on the edge of the bridge where the rubber bands can rest.
Refer to illustration for a basic idea on what your matchbox guitar should look like.
Observation
What else could you have used in this experiment to create a more varied sound on
your matchbox guitar? Do you think you can use some of the principles you've learned
here to create a bowed string (violin, cello, etc) instrument out of some common
household items?
Result
The matchbox guitar is an example of a plucked string instrument, which also includes
mandolins, balalaikas, and bass guitars. The instrument works by plucking the string
with your finger tips. The different pitches are created by placing your finger at
different points along the string to either shorten the pitch or lengthen it based on the
vibration. The strength at which the strings are plucked also affects the frequency and
pitch of the sound as it can create a larger vibration or a smaller vibration.

6. Vibrating Coin
Purpose
To demonstrate the expansion of air when heated.
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 known as
thermal expansion.
Required materials
 Coin
 Bottle
 Refrigerator
 Water
Estimated Experiment Time
Approximately 15 to 20 minutes
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

7. 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.
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.
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.