Cannon Design

Last physics class, we were told to design a cannon out of a possible of 8 cans that would fire a Styrofoam cup using only 2 ml of fuel. The cannon would be fired off a table and be graded based on the maxium x component; the distance of travel. So, for my design, I had to consider some factors

1. The angle at which it would be launched

2.The baffles to maximize pressure to shoot the cup

3. A way to decrease back fire (Just in case)

4. The fact that it would be fired off an elevated surface 

With these factors in mind, I created a flat cannon in the sense that the cannon has minimal to no angle and will be fired flat against the table. Although all the other groups created an angle of 45 degrees, this angle was best suited for case 4 projectiles; for projectiles that will start and end at the same level/height. Since my cannon will be fired on an elevated surface, it is pointless to fire it at an angle since the cannon will be wasting it's fuel trying to accelerate upwards rather than distance-wise, which is what I will be graded for Figure 1.

For the cannon itself, I used a large can, a medium and then a small one Figure 1. This was so the pressure would build up and then center itself behind the Styrofoam cup so it can be fired out. Also, the baffles are small holes distributed like a pinwheel so the pressure could be distributed even around the can instead of on one side Figure 2.

To decrease backfire and ensure that the cannon will not waste it's energy backfiring, I created a hook out of one of the empty cans and attached it to the cannon. The hook would hang over the edge of the table Figure 3.

Figure 1. Finished Cannon
Big to small cans to center pressure
Flattened can to ensure cannon will not move when being fired
Can hook to decrease backfire and wasted energy

Figure 3. Cannon Hook
Will be hooked onto testing surface to decrease backfire

Figure 2. Baffles

Golf Range

The History of Flying Machines

 

Airplanes, helicopters, jets and air balloons, what do they all have in common? You guessed it! They are all flying machines. Flying machines have changed the way we transport things and has made the world more like global village.

Leonardo De Vinci (1452-1519)

Drawing of Leonardo's Human-Powered Ornithopter,  a wing-flapping device intended to fly, in 1485 

Let's begin with Leonardo De Vinci, the Italian "dreamer" of flying machines. He created multiple drawings of flying contraptions using his knowledge of how birds and bats flew (Gray, C. 2006). Although there is no evidence that he attempted to make any of his drawings, his drawings and ideas allowed man to become one step closer to flying.

Sir George Cayley (1773-1857)

 Sir George Cayley built contraptions himself and were successful in only a few short flights. Although, he his credited for stating that lift, propulsion and control were the three requisite elements to successful flights (Gray, C. 2006) .

Monoplane glider in 1848

In 1878, Charles F. Ritchel created the "Ritchel Flying Machine" that was hand- cranked and was capable of keeping a float for over an hour (Gray, C. 2006). It was the first flying machine that was demonstrated in public and was flown in Connecticut, Pennsylvania and Massachusetts. Five of these machines were sold.

Break down of Ritchel Flying Machine

Ritchel Flying Machine Drawing

John J. Montgomery 1858-1911

1884 monoplane with curved wings

Top: 1885 monoplane with flat wings
1886 monoplane with adjustable wings

 

 John J. Montgomery began his own aerial experiments in 1883. His first monoplane glider was built in 1884 and had curved wings, it flew from Otay Mesa, San Diego to California  (Gray, C. 2006) . He built another monoplane in 1884-1885 and this time it had flat wings. 1886 was his turkey inspired plane in which it has adjustable wings to ensure balance in flight  (Gray, C. 2006) . It is believed that Montgomery recorded the circulation of water around his test surfaces therefore suggesting that he experienced "circulation theory of lift". 

Daniel J. Maloney

1896 Santa Clara Glider

 Daniel J. Maloney was a professional parachutist who was brave enough to test fly Montgomery's flying machines. He was able to maneuver the planes quickly but a fatal accident in July 1905 caused his death when he was flying the "Santa Clara, Montgomery's fourth glider that could carry humans and had a 24 ft wing span (Gray, C. 2006). The Santa Clara was built in 1896 and another was built in 1903 called the "California". 

The most well known pair for flight are the Wright brothers, Orville and Wilber. They obtained flight knowledge through research of other inventors and studying balloons and kites. Once they gathered enough information, they developed test gliders that could be controlled. They found the glider that would consistently fly during their tests but needed a way to produce enough power to lift it into the air therefore they created an engine that has 12 horse power.

The 12 horsepower engine

 The "Flyer", weighing 605 pounds, flew on December 17, 1903 at 10:35 am and it was Orville who was credited for the first flight (Shaw, R. n.d).

Flight of "Flyer"

Due to all the dreamers, researchers, inventors and creators, we are capable of having human flight in modern times. We now have a fast, efficient and relatively safe way to transport people, cargo and objects over long distances in a short amount of time 

   

Works Cited

1. Gray, C. (2006, December 19). FLYING MACHINES - John J. Montgomery. The FLYING MACHINES Web        Site. Retrieved March 24, 2012, from http://www.flyingmachines.org/mont.html 
2. Shaw, R. (n.d.). History of Flight. UEET Kid's Site. Retrieved March 24, 2012, from http://www.ueet.nasa.gov/StudentSite/historyofflight.html 

Right Hand Rule #2 for Conventional Current Flow

RHR#2 positioning on coiled conductor
Thumb points to North end of electromagnet

Coiled conductor and its magnetic field

An easy method of determining the magnetic field and the north and south ends of an eletromagnet produced by a coil is using the right hand rule #2 for conventional current flow, also known as RHR#2. Grasp the coiled conductor in such a way that your fingers curve in  the direction of conventional current, from positive to negative. The direction where your thumb extends to is the north (N) end of the electromagnet produced by the coil.

Earth's Magnetic Field

A compass points north because it is
attracted to the south pole of earth's magnet

 

 

 

 

 

 

Comparison between the placement of the
Magnetic Poles and the Geographical Poles

The earth is a giant magnet in which there is a north pole and south pole. In geograpghy class, students are taught geographical north and south poles where the north pole is at the top and the south pole is at the bottom of the earth. The "north" and "south" poles of the earth gives people direction and therefore, are given the names true north and true south. On the contrary, magnets have a north and south poles in which north is attracted to south and south is attracted to north. Therefore if a compass points north, the compass is actually attracted to the south magnetic pole of the earth. In actuality, with the science and physics of a magnet, the poles of earth are switched and the north pole is the south pole of a magnetic and the south pole is the north pole of a magnetic. These scientific poles are called magnetic south, which is the north pole, and magnetic north, which is the south pole. It can also be called Earth's south and Earth's north. But how can people differentiate between these two and which one is more reliable than the other? Geographical/ true north & south are more reliable because they are situated at the top and bottom of the earth unlike magnetic/ Earth's north & south, which is tilted at an angle and continues to tilt and change angles. In summary, in a geographical sense, the north pole is called the geographical north and the south pole is called the geographical south. Opposites attract so if the compass points north, that means it is attracted to a south charge therefore the north pole is actually magnetic south or Earth's south and the south pole is magnetic north or Earth's north.

Magnets can also lose their north and south magnetic properties when they are heated, therefore the Earth's inner core does not have magnetic forces. Although, one theory believes that the inner core, composed of liquid iron, eletrically conducts the magnetic properties of earth's pole. Additionally, it is at the equator that the magnetic field is perfectly parallel to earth's surface, the angle of difference between other areas, other than the equator, is called magnetic declination.

Works Cited

Castleman, A. (2008, February 28). The Earth Has More Than One North Pole: Scientific American. Science News, Articles and Information | Scientific American. Retrieved February 25, 2012, from http://www.scientificamerican.com/article.cfm?id=the-earth-has-more-than-one-north-pole

Mista, C. (2011, November 23). This is a password protected video on Vimeo. Vimeo, Video Sharing For You. Retrieved February 25, 2012, from http://vimeo.com/29641648

Russell, R. (2009, April 17). Earth's North Magnetic Pole. Windows to the Universe. Retrieved February 25, 2012, from http://www.windows2universe.org/earth/Magnetosphere/earth_north_magnetic_pole.html

My Energy Ball

The Energy Ball Report

Figure 1. Series Circuit (6)

Figure 2. Parallel Circuit (2)

Figure 3. Electrolytes in the Human Body (5)

Figure 1 is a series circuit. A series circuit is a closed circuit in which there is only one path that the electrons can flow through between any two points therefore the electrons must flow through all the loads (6). Furthermore, when the circuit becomes an open circuit due to a break or opening in the series circuit, the entire circuit does not operate because the flow of electrons passing through the circuit is stopped when it reaches the break or opening in the series (7). For visual sense, if the wire was disconnected between bulbs one and two, it would be an open circuit in which the electrons cannot flow thorough the bulbs, hence neither bulb will flash. On the other hand figure 2 is a parallel circuit. A parallel circuit is two or more series circuits connected together which means multiple pathways where the electron current can flow through. This allows the electron current to flow through one load without affecting the other load and, as a result, if there is a break or opening in the circuit, resulting in an open circuit, it will not affect the operation of the entire circuit, unlike the series circuit (3).

Human bodies are natural conductors due to the ions therefore allowing the electrons to flow through the body (2). The human body’s fluids consist of water and electrolytes, refer to figure 3 (5). Electrolytes, also known as ions, are atoms that have either a positive or negative charge due to the gain or loss of electrons. Due to the positive or negative charges in the body’s fluids, it allows a current of electrons to flow through the body (5). The only logical possibility in which the energy ball does not work on an individual would be there is a presence of an insulator therefore inhibiting the flow of electrons. Insulators are materials that have low conductivity that, when a current flows through them, the current is negligible (4). The person could possibility be wearing rubber gloves, which are insulators, thus making the energy ball not work because the current through the rubber gloves is so low that the electrons cannot be conducted to complete the flow of electrons in the circuit. 

During this assignment, I solidified my knowledge over the differences between a series and parallel circuit and understand how an open circuit can cause a series circuit to stop operating all together while a parallel circuit can still operate through the other pathways. I also learned how there are electrolytes in the human body which are the main causes of electric conductivity in humans. For the learning skills, I learned responsibility by completing this assignment by the due date and organization by organizing my schedule and time for this report. I worked independently and collaborated my previous knowledge as well as the discussions in class and verified my statements with reliable internet resources. I had the initiative to complete this assignment independently and self educated myself in this course. Furthermore, I self regulated by periodically checking my work and self accessing the quality of this paper.

References

1. Cew. (n.d.). Parallel Circuits. Instructables - Make, How To, and DIY. Retrieved February 8, 2012, from http://www.instructables.com/id/A-Complete-Guide-To-Basic-Electronics/step3/Parallel-Circuits/

2. Heller, J. (2012, January 26). Electrical injury: MedlinePlus Medical Encyclopedia. National Library of Medicine - National Institutes of Health. Retrieved February 8, 2012, from http://www.nlm.nih.gov/medlineplus/ency/article/000053.htm

3. Henderson, T. (n.d.). Parallel Circuits. The Physics Classroom. Retrieved February 8, 2012, from http://www.physicsclassroom.com/class/circuits/u9l4d.cfm

4. Insulators. (n.d.). Dictionary.com Unabridged. Retrieved February 08, 2012, from Dictionary.com website: http://dictionary.reference.com/browse/insulators

5. Its Electrifying! Electrical Signals in the Human Body. (2010, September 3). Home for HASPI, San Diego's Health and Science Pipeline Initiative.. Retrieved February 8, 2012, from http://haspi.org/curriculum-library/MedicalChemistry/00%20Medical%20Chemistry%20Core%20Labs/02ab_Core%20Lab__It's%20Electrifying!%20Electrical%20Signals%20in%20the%20Human%20Body.pdf

6. Ruth, J. (n.d.).  circuit .  Laurier Elementary . Retrieved February 8, 2012, from http://lau.vsb.bc.ca/studentp/judyruth/circuit.html

7. Series Circuit. (n.d.). Fundamentals of Electricity. Retrieved February 8, 2012, from http://epb.apogee.net/foe/fcsps.asp

8. The Series Circuit. (n.d.). NDT Research Centre. Retrieved February 8, 2012, from http://www.ndt-ed.org/EducationResources/HighSchool/Electricity/seriescircuit.htm