EXPERIMENT ON HOW DIFRENT AMOUNTS OF PUMPS AFFECT HOW FAR A NERF BULLET FLYS
Parker Courts
Cary Academy
ABSTRACT
The purpose is to shoot a nerf gun with various numbers of pumps and see which one flies the
farthest. Projectile motion has to do with this because it is what makes the nerf bullet decrease
in speed and stop. The method is to shot a nerf bullet that is soaked in water for different
times and see which nerf bullet flies the farthest. The results were that the bullet soaked in 2
min 30 sec flew the farthest. The more time the bullet is soaked in the water, the faster it flies
because the nerf bullet releases quicker from the pocket because it is more slippery and it is
denser.
INTRODUCTION:
Gravity is a force that pulls two objects towards each other. The bigger the object is, the more
gravitation pull it has. Gravity is a part of the four fundamental forces of nature along with
nuclear strong force and weak force, and electromagnetism. Any mass in the world has a
gravitational pull. Without gravity everything would be floating in air right now, but since
humans have gravity things that go up in the air come down. Many things in this world would
be different without gravity; like people would have no weight and everything would be
floating right now. The basic point of gravity is that if something goes up in the air it will always
come down. Without gravity that objects would float. One formula is force=mass*
acceleration. The mass in which case an apple can be used for an example. If this apple is 100
grams and the apple is traveling 10 meters per second squared. To stop the apple a person has
to have the same force of hand and the same force of gravity. This will make the apple level.
Isaac newton came up with a formula of gravity which is GMm/R2 G stands for gravitational
constant. M stands the mass of the body, and Distance between the two masses better known
then the radius. If a person’s mass and the distance to the center of the earth people can
calculate how much the earth ways. After this Albert Einstein made a more perfections version
and it is now counted on more than Isaac newton’s theory.
AIR PRESURE
Air pressure
compartmen
t
Pump
Air pressure is a force exerted by a column into a certain location. When two molecules
collided together, they push out air pressure. More air pressure is made by putting more
molecules into a container, or by releasing molecules, air pressure can be let go. If the
temperature is either lowered or raised the molecules will either stop moving, or start moving
faster when air is being heated it rises in the air, but when it is being cooled the air presses
down on the ground and rises into the air creating more air pressure. Air pressure is measured
by a device called a barometer. Android and mercury barometers are the most popular but
many more exist and are not as often used. The android barometer uses a sylphon cell to
measure air pressure. The android barometer expands and contracts, by doing this it changes
air pressure. The mercury barometer stores mercury at one end of a tube. The air pressure
pushes the mercury towards the top of the barometer and then you measure the air pressure in
a certain area. Scientist will typically use millibars to measure barometers. 1013.2 is your
average air pressure. Any above that is considered high air pressure. Anything below is
considered low air pressure. You would think air pressure rises when it moves up wards, but it
actually lowers because the air Colum shortens and there is less mass for the air to push of off.
Sea level air pressure is used to even out or differ ate high air pressure and low air pressure.
Isobars are used to connect points of equal lines of air pressure on height maps. These are
used by meteorologist. The consistent pressure map also analyzes air pressure. On the isobar
surface 500 mb is a constant and typical pressure surface.
PROJECTILE MOTION
Projectile motion sounds complicated, but all it is 3-d motion. Parabola is another name for
projectile. Parabola is a curve that happens when an object is thrown into the air and lands in a
different place then it was throw. Trajectory is a curve that happens after parabola is in effect.
Galileo believed that horizontal and vertical angles make up projectile motion. At first if you
throw a ball it goes horizontal, but when the ball drops that is the vertical motion gowning
downwards. If you throw the ball diagonally up in the air the ball will not travel as far because
it does not make a horizontal movement. It just goes up in the air and comes back down at an
angle. Other than parabola there is another type of movement called kinematics. Kinematics is
the scientific definition describing motion. There are two important words for kinematics, they
are scalars and vectors. Vectars are described by magnitude and direction in quantities. Scalars
are quantities that describe their numeral value or magnitude. Isaac New tans laws of motion
play a role in projectile motion too. The laws state that when an object is in motion it stays in
motion in till it is stopped by external force.
WHAT EXPERIMENTS HAVE BEEN DONE BEFORE
Chandler C did an experiment on the study of how well projectiles fly from a catapult relating to
their shape and mass. The main goal of his experiment was to find out the maximum flying
distance of projectiles that varied in weight. He set up a catapult and weight different
projectiles. Then he catapulted them to test their velocity. He said that the smaller the
projectiles are the faster they would go and he was correct on his hypothesis.
MATERIALS AND METHODS
Materials: Nerf gun, nerf bullets, meter sticks, beaker, water, and a stool
Experiment 1: To pump the nerf gun x amount of times more every time that the nerf gun is
shot and measure the increase and how far the nerf bullet flies compared to lesser pumps and
more pumps.
Experiment 2: To pump the nerf gun 4 times and angle the nerf gun each time. The angels will
be flat, 2cm, 4cm, and 6cm, 8cm, 10cm
Experiment 3: Method- to shoot the nerf gun at different walls or surfaces and measure how far
it bounces back.
Experiment 4: the nerf gun at 1 surface from five different distances
Experiment 5: to shoot a nerf bullet at a locker from 4 meters and pumps it 1,2,3,4 and five
times
Experiment 6: To dip a bullet in water and leave it in the water for x amount of seconds the nerf
gun. I will use the times of 0 sec, 30 sec, 1 min, 1 min 30 sec, 2 min,
distance nerf bullet flew (m)
RESULTS AND DISCUSIONS
16
14
12
10
8
6
4
2
0
0
2
4
6
amount of pumps
Figure 1 does the amount of impacts affect how far the nerf bullet flies.
8
The nerf bullet acierates and flies farther when there are more pumps. The amount the first
nerf bullet flew was 3 meters then it increased up to 15 meters. By pumping the nerf gun more
times it can make a big impact on how far it flies.
distance nerf bullet flew (m)
16
14
12
10
8
6
4
2
0
0
1
2
3
4
5
angle of nerf gun (cm)
Figure 2 does the angle of the nerf gun affect how far the nerf bullet flies.
The angles made a big impact on how far the nerf bullet flew. The bullet increased in length it
flew every time I moved the angle up. If the angle of the nerf gun was too high then eventually
the bullet will get more height than length.
Distance bullet bounced back of the
surface
200
180
160
140
120
100
80
60
40
20
0
0
1
2
3
4
5
6
difrent surfaces
Figure 3 the distance bounced back of the surface.
The nerf bullet bounced back different distances of different surfaces. Some surfaces were
better for the bullet and some weren’t Some surfaces like wood did not work as well because it
is very hard and does not give the bullet a spring or push when it flies back.
distnace nerf bullet bounced back (cm)
250
200
150
100
50
0
0
1
2
3
4
5
6
number of pumps
Figure 4 does the amount of pumps used to make the nerf bullet bounce back father off the wall.
Overall the more number of pumps I added made the nerf bullet bounce back. The locker was
metal and the nerf bullet bounces back of the metal easier than any other surface. Every
different time I shot the nerf gun and added more pumps, the more pumps I added the bullet, it
bounced back about 30 cm more.
Distance nerf bullet bounced back (cm)
160
140
120
100
80
60
40
20
0
0
0.5
1
1.5
2
2.5
3
3.5
distance away from wall (m)
Figure 5 does the distance away from the wall affect how far the nerf bullet bounces back.
The closer that the gun got to the wall the nerf bullet bounced back farther. The father away I
got from the wall the bullets didn’t bounce back as far because the force that the bullet hit the
wall with decreases every time that I move back.
distance nerf bullet flew (m)
14
12
10
8
6
4
2
0
0
0.5
1
1.5
2
time soaked in water (minuts)
Figure 6 does the time a nerf bullet is soaked in water affect how far it flies.
2.5
The more time that the bullet was soaked in water the bullet got wet and it was slippery,
therefor easier to come out of the pocket when firing the nerf gun. The bullet also got denser
so the bullet flew better. When the bullet gets denser the air cannot seep through the bullet
therefore the bullet doesn’t absorb the air and flies better.
CONCLUSION
In the last experiment the bullet soaked in water the longest flew faster and longer than any
other bullet. The hypothesis was correct because it says thought the bullet soaked in water for
the longest would fly the farthest. The results are important because this experiment was
completely different than all the other experiments. For a future experiment I could soak a
bullet in water for the same amount of time but use different amounts of pumps to shoot the
nerf gun.
http://www.qrg.northwestern.edu/projects/vss/docs%20/space-environment/1-what-is-gravity.html
http://coolcosmos.ipac.caltech.edu/ask/300-What-is-gravityhttp://www4.uwsp.edu/geo/faculty/ritter/geog101/textbook/circulation/air_pressure_p_1.html
Erik gregersen physics explained, Britannica Rosen educational service. 2011, Ney York.
Physical forces.
http://researchthetopic.wikispaces.com/What+is+projectile+motion%3F+Part+1