Cannons were used in the past as artillery. It uses gunpowder to launch projectiles and the amount of gunpowder varies according to how much power is required. The angle of the cannon to the surface of the ground also varies because it is measured to the desired angle for firing a certain distance or height. Cannons are similar to guns but obviously at a larger scale in terms of size.
So how does a cannon work?
Cannons are composed of a large barrel with one open end. It works through the pressure at the closed end produced by the gunpowder or explosive. This force of pressure pushes out the projectile out of the open end.
As we already know, the pressure does not necessarily have to come from gunpowder, it can also function through the pressure of air, which is used for tennis balls. Yes, that's right. We use cannons in our daily lives as well, not just in the past for wars.
Thursday, April 28, 2011
Calculations for the Lab: Force, Acceleration, and Mass
F a (m/s^2)
1 2.61
2 5.46
3 5.60
m a (m/s^2)
0 2.28
1 3.19
*one of them was eliminated as it was a repeated experiment
1 2.61
2 5.46
3 5.60
m a (m/s^2)
0 2.28
1 3.19
*one of them was eliminated as it was a repeated experiment
Our Tallest Structure
I suppose you could say we were quite surprised that we managed to build the tallest structure, though it was a great feeling of success! However, although it managed to stand up, it was extremely unstable. Dennis' idea of building a big base in a pyramid set up was a good idea, but when it came down to actually rolling up the pieces of newspaper to make our structure, we realized that some of the pieces of newspaper were shorter and thinner while others were larger and thicker. Therefore, the bottom was uneven causing it to be very shaky and not stand properly. Nevertheless, we managed to balance it by shortening our tall thin tube and slowly bringing it up every time we thought our structure could handle the extra height. We even added a tape-flag-thing to add a couple centimeters of height to our strucutre.
Now I think we can all conclude that newspaper and tape aren't exactly the best materials for building structures, even if it's just for an in class task.
Now I think we can all conclude that newspaper and tape aren't exactly the best materials for building structures, even if it's just for an in class task.
Tallest Tower?
According to my research, Burj Khalifa is the tallest man-made tower in the world with a height of 828 m!!!
However, I did not know that till I researched it up. The first thing that came to mind when "tallest tower" was mentioned was the CN Tower.
Although it isn't the tallest structure, the structural concept is somewhat similar. The base is obviously the largest, holding up and supporting the whole weight of the building, while the top is extremely thin and small. As we learned recently, the centre of gravity is what supports the weight. Though in different objects, the centre of gravity varies, in buildings it is probably the centre and at the base of the structure. That's my assumption, but it's an educated guess and an obvious answer, unless of course I'm wrong. In terms of building our tower, I think we should have one realllllllyyyyyy long, but thin tube that will give our structure the height, supported by a large, heavy base... even though it's only newspaper.
However, I did not know that till I researched it up. The first thing that came to mind when "tallest tower" was mentioned was the CN Tower.
Although it isn't the tallest structure, the structural concept is somewhat similar. The base is obviously the largest, holding up and supporting the whole weight of the building, while the top is extremely thin and small. As we learned recently, the centre of gravity is what supports the weight. Though in different objects, the centre of gravity varies, in buildings it is probably the centre and at the base of the structure. That's my assumption, but it's an educated guess and an obvious answer, unless of course I'm wrong. In terms of building our tower, I think we should have one realllllllyyyyyy long, but thin tube that will give our structure the height, supported by a large, heavy base... even though it's only newspaper.
Tuesday, April 5, 2011
Egg Glider
Our group doesn't have an idea but I guess we'll all come up with our own and bring it together soon. I'm not too familiar with aerodynamics and things like that, but from what I remember, I know that it has to be shaped somewhat like a paper airplane or a kite. I'm guessing that a point at the front (which the both the kite and paper airplane have) is something that will help with the egg glider's ability to glide. Last but not least, I know for a fact that both sides have to be symmetrical in order for it to glide straight.
But from what I've briefly researched on Google, aerodynamics is something designed to minimize the drag as an object moves through gas or liquid.
Now you may ask, "What does drag mean?"
Drag is air resistance or friction, where it slows down the object as it moves through gas or liquid.
So I guess my ideas are like a kite or a plane with the sheet of newspaper as the "wing" or surface area and the straws as supports. Now for the real question, how will the egg be protected while still allowing the glider to glide...? Maybe some sort of cone made out of the straws so that when the cone hits the ground, the force will transfer from the tip of the cone and pass right around the egg to the end of the cone. But I don't have a clue as to how to make that support aerodynamic as well. Maybe there is no way.
But from what I've briefly researched on Google, aerodynamics is something designed to minimize the drag as an object moves through gas or liquid.
Now you may ask, "What does drag mean?"
Drag is air resistance or friction, where it slows down the object as it moves through gas or liquid.
So I guess my ideas are like a kite or a plane with the sheet of newspaper as the "wing" or surface area and the straws as supports. Now for the real question, how will the egg be protected while still allowing the glider to glide...? Maybe some sort of cone made out of the straws so that when the cone hits the ground, the force will transfer from the tip of the cone and pass right around the egg to the end of the cone. But I don't have a clue as to how to make that support aerodynamic as well. Maybe there is no way.
Saturday, March 26, 2011
Kinematics Homework pg. 72
question 58 was a bit confusing....
(for some reason the picture doesn't appear but if you click it, the picture alone will appear)
Kinematics Graph Translations (lab results)
My original plan was to have my translated graphs placed after the computer given/walked graphs but this blog is very stubborn and will not let me and I have lost the energy to redo everything AGAIN, so here it is:
   |
| Graph 01b |
 |
| Graph 01c |
 |
| Graph 01d |
 |
| Graph 01e |
 |
| Graph 01f |
Tuesday, March 8, 2011
Kinematics Graphs
Today, we used motion detectors and a graph program to do our lab activity. We were given graphs, either distance vs time or velocity vs time, and we had to walk them accordingly. Though I wasn't too excited to do this lab at first, due to all the graphs we had to "describe" as a pre-lab activity yesterday, my feelings had changed during and after the lab. To me, this wasn't just a lab, it was a game. It was a game to beat everybody else's ability to match the graph and make mine better. Though it seems like a childish goal, it was still something I felt I HAD to achieve. In the end, I had one amazing graph that was almost IDENTICAL to the given graph. I must say, I am quite proud of myself.
The black line represents the given graph that must be matched and the red line represents the graph that one has walked.
The black line represents the given graph that must be matched and the red line represents the graph that one has walked.
(for some reason, the x axis seems to have disappeared)
To walk these graphs, you would have to start at the given position (a certain distance away from the origin or from the motion detector) and walk towards or away from that origin. The velocity may be consistent or may increase/decrease and sometimes you may have to stop. These factors all vary as the graphs are different and have different variables.
Right Hand Rules #1 and #2
Finding current and magnetism would be difficult without these visual, hands-on actions to help one solve the current and magnetism of conventional current flow for conductors (RHR#1) and coiled conductors/solenoids (RHR#2).
*note, all of these should be done with the RIGHT HAND, hence the name/title of these rules
RIGHT HAND RULE #1
Hold the conductor with the thumb pointing towards the direction of the conventional current flow (from +ve to -ve). The rest of your fingers should curl around the conductor and these curved fingers will point to the direction of the magnetic field of that conductor.
Current is represented by I and the magnetic field is represented by B.
RIGHT HAND RULE #2
Hold the coiled conductor with the rest of the fingers (meaning excluding the thumb) pointing towards the direction of the conventional current flow. The thumb should point to the direction of the magnetic field within the coil. On the outside of this coil, the thumb points towards the north pole of the electromagnet. This electromagnet follows the same lines of force/magnetic field lines as a normal magnet. The current flow from the north pole to the south pole in curved lines.
*NOTE:
Therefore, when using this for RHR#1, point thumb towards you or away from you to figure out the magnetism.
*note, all of these should be done with the RIGHT HAND, hence the name/title of these rules
RIGHT HAND RULE #1
Hold the conductor with the thumb pointing towards the direction of the conventional current flow (from +ve to -ve). The rest of your fingers should curl around the conductor and these curved fingers will point to the direction of the magnetic field of that conductor.
Current is represented by I and the magnetic field is represented by B.
RIGHT HAND RULE #2
Hold the coiled conductor with the rest of the fingers (meaning excluding the thumb) pointing towards the direction of the conventional current flow. The thumb should point to the direction of the magnetic field within the coil. On the outside of this coil, the thumb points towards the north pole of the electromagnet. This electromagnet follows the same lines of force/magnetic field lines as a normal magnet. The current flow from the north pole to the south pole in curved lines.
*NOTE:
Therefore, when using this for RHR#1, point thumb towards you or away from you to figure out the magnetism.
Thursday, February 24, 2011
The Top 10 Things You Need To Know About Grade 11 Electricity (according to TDSB standards)
Now, young grasshopper, in order to become a master of the unit ELECTRICITY, there are a few things that you must know. In fact, these might be the top 10 things that you should know in case you may encounter obstacles or rather tests in your life. However, you must only use this knowledge for good.
1. the difference between conventional current and electron flow; conventional current moves from +ve to -ve and electron flow moves from -ve to +ve
2. equation for current: I = Q/t ; where I is current measured in amperes (A), Q is the charge in Coulombs (C), and t is the time in seconds
3. one electron is the equivalent to 1.6 x 10-19 C and one Coulomb is the equivalent to 6.25 x 1018 electrons
4. the difference between series circuits and parallel circuits (and possibly how it affects the world) *keep in mind that a circuit with both series and parallel circuits are called complex circuits
5. equation for potential difference: V = E/Q; where V is voltage/potential difference measured in volts (V), E is the energy or work in joules (J), and Q is the charge in Coulombs (C)
6. Ohm's Law and Kirchhoff's Law and their relationship --> with this you must be able to solve the CURRENT, VOLTAGE/POTENTIAL DIFFERENCE, and RESISTANCE in a circuit
7. how to add voltmeters and ammeters in a circuit; voltmeters are used in parallel circuits and ammeters are used in series circuits
8. equation for power: P = IV or P = V2/R or P = I2R; where P is power in watts (W) and R is resistance in ohms (Ω)
9. how to figure out the overall resistance when given a colour band resistor (recall: the gold or silver band should always be at the end to indicate the percent error and the last colour before the gold or silver band is the exponent of the power with a base of 10)
10. how to draw/make or read graphs and being able to calculate the slope! SLOPE = RISE/RUN (don't forget to have a detailed title and include labels for the axes with the units)
and that, my young grasshopper, is what you need to know for ELECTRICITY
1. the difference between conventional current and electron flow; conventional current moves from +ve to -ve and electron flow moves from -ve to +ve
2. equation for current: I = Q/t ; where I is current measured in amperes (A), Q is the charge in Coulombs (C), and t is the time in seconds
3. one electron is the equivalent to 1.6 x 10-19 C and one Coulomb is the equivalent to 6.25 x 1018 electrons
4. the difference between series circuits and parallel circuits (and possibly how it affects the world) *keep in mind that a circuit with both series and parallel circuits are called complex circuits
5. equation for potential difference: V = E/Q; where V is voltage/potential difference measured in volts (V), E is the energy or work in joules (J), and Q is the charge in Coulombs (C)
6. Ohm's Law and Kirchhoff's Law and their relationship --> with this you must be able to solve the CURRENT, VOLTAGE/POTENTIAL DIFFERENCE, and RESISTANCE in a circuit
7. how to add voltmeters and ammeters in a circuit; voltmeters are used in parallel circuits and ammeters are used in series circuits
8. equation for power: P = IV or P = V2/R or P = I2R; where P is power in watts (W) and R is resistance in ohms (Ω)
9. how to figure out the overall resistance when given a colour band resistor (recall: the gold or silver band should always be at the end to indicate the percent error and the last colour before the gold or silver band is the exponent of the power with a base of 10)
10. how to draw/make or read graphs and being able to calculate the slope! SLOPE = RISE/RUN (don't forget to have a detailed title and include labels for the axes with the units)
and that, my young grasshopper, is what you need to know for ELECTRICITY
Concept Map
Although one may believe that a more visual method of studying would be helpful, I somewhat agree and disagree. I guess you could say it depends on the way you have studied in the past (whether or not you constantly used one method of studying and adapted to that method) or simply the type of learner you are. I think that this concept map is somewhat too confusing for me. Maybe using this concept map for a brainstorm or review of everything I've learned might be helpful, but for me, rewriting out what I've learned on a piece of paper or making cue card notes is best for me. However, I won't say that I completely think that this method is useless to me, but a new method that maybe I just need to get used to. Who knows, it might end up becoming my best studying method yet, but I guess I'll have to adapt to it first.
Saturday, February 12, 2011
Ohm and Kirchhoff
Ohm's Law
Georg Simon Ohm (1787-1854) found that the ratio Potential Difference (in volts)/ Current (in ampere) [V/I] was constant for a specific resistor. This means that even if more energy sources were added on to the circuit, the quotient of the potential difference divided by the current would be the same. This relationship is known as being directly proportional which is represented by the sign "α" (lowercase alpha).
V α I
What does directly proportional mean? It basically means that when one variable goes up, the other variable goes up as well, and when one variable goes down, the other variable goes down as well. In our case, the two variables are POTENTIAL DIFFERENCE (V) and CURRENT (I).
Furthermore, current is inversely proportional with resistance which means that when the current goes up, the resistance goes down, and when the current goes down, the resistance goes up. It is represented by the following:
I α 1/R
Ohm's law can be represented by the mathematical triangle:
(*note: when looking for the current, cover I and you are left with V/R, when you are looking for the resistance, cover R and you are left with V/I, and when you are looking for the potential difference, cover V and you are left with IR [multiply])
Kirchhoff's Law
Gustav Robert Kirchhoff (1824-1887) came up with the two laws about current and voltage.
Current: "The total amount of current into a junction point of a circuit equals the total current that flows out of that same junction."
Voltage: "The total of all electrical potential decreases in any complete circuit loop is equal to any potential increases in that circuit loop."
CURRENT (I)
SERIES
IT = I1 = I2 = I3 = … = In
PARALLEL
IT = I1 + I2 + I3 + … + In
VOLTAGE/POTENTIAL DIFFERENCE (V)
SERIES
VT = V1 + V2 + V3 + … + Vn
PARALLEL
VT = V1 = V2 = V3 = … = Vn
WITH OHM'S LAW AND KIRCHHOFF'S LAW IN MIND, Resistance can be solved mathetmatically using both laws.
RESISTANCE (R)
Georg Simon Ohm (1787-1854) found that the ratio Potential Difference (in volts)/ Current (in ampere) [V/I] was constant for a specific resistor. This means that even if more energy sources were added on to the circuit, the quotient of the potential difference divided by the current would be the same. This relationship is known as being directly proportional which is represented by the sign "α" (lowercase alpha).
V α I
What does directly proportional mean? It basically means that when one variable goes up, the other variable goes up as well, and when one variable goes down, the other variable goes down as well. In our case, the two variables are POTENTIAL DIFFERENCE (V) and CURRENT (I).
Furthermore, current is inversely proportional with resistance which means that when the current goes up, the resistance goes down, and when the current goes down, the resistance goes up. It is represented by the following:
I α 1/R
Ohm's law can be represented by the mathematical triangle:
(*note: when looking for the current, cover I and you are left with V/R, when you are looking for the resistance, cover R and you are left with V/I, and when you are looking for the potential difference, cover V and you are left with IR [multiply])
Kirchhoff's Law
Gustav Robert Kirchhoff (1824-1887) came up with the two laws about current and voltage.
Current: "The total amount of current into a junction point of a circuit equals the total current that flows out of that same junction."
Voltage: "The total of all electrical potential decreases in any complete circuit loop is equal to any potential increases in that circuit loop."
CURRENT (I)
SERIES
IT = I1 = I2 = I3 = … = In
PARALLEL
IT = I1 + I2 + I3 + … + In
VOLTAGE/POTENTIAL DIFFERENCE (V)
SERIES
VT = V1 + V2 + V3 + … + Vn
PARALLEL
VT = V1 = V2 = V3 = … = Vn
WITH OHM'S LAW AND KIRCHHOFF'S LAW IN MIND, Resistance can be solved mathetmatically using both laws.
RESISTANCE (R)
SERIES
VT = V1 + V2 + V3 + … + Vn
(using Ohm’s Law we know V= IR)
ITRT = I1R1 + I2R2 + I3R3 + … + InRn
(which can be written as)
ITRT = ITR1 + ITR2 + ITR3 + … + ITRn
ITRT = IT(R1 + R2 + R3 + … + Rn)
(IT can be crossed out, which is represented by the red)
ITRT = IT(R1 + R2 + R3 + … + Rn)
RT = (R1 + R2 + R3 + … + Rn
PARALLEL
IT = I1 + I2 + I3 + … + In
(using Ohm’s Law we know I= V/R)
VT /RT = V1/R1 + V2/R2 + V3/R3 + … + Vn/Rn
(which can be written as)
VT /RT = VT/R1 + VT/R2 + VT/R3 + … + VT/Rn
(Multiply by 1/VT in order to isolate R)
(1/VT) (VT/RT) = (1/VT) (VT/R1 + VT/R2 + VT/R3 + … + VT/Rn)
1/RT = 1/R1 + 1/R2 + 1/R3 + … + 1/Rn
VT = V1 + V2 + V3 + … + Vn
(using Ohm’s Law we know V= IR)
ITRT = I1R1 + I2R2 + I3R3 + … + InRn
(which can be written as)
ITRT = ITR1 + ITR2 + ITR3 + … + ITRn
ITRT = IT(R1 + R2 + R3 + … + Rn)
(IT can be crossed out, which is represented by the red)
ITRT = IT(R1 + R2 + R3 + … + Rn)
RT = (R1 + R2 + R3 + … + Rn
PARALLEL
IT = I1 + I2 + I3 + … + In
(using Ohm’s Law we know I= V/R)
VT /RT = V1/R1 + V2/R2 + V3/R3 + … + Vn/Rn
(which can be written as)
VT /RT = VT/R1 + VT/R2 + VT/R3 + … + VT/Rn
(Multiply by 1/VT in order to isolate R)
(1/VT) (VT/RT) = (1/VT) (VT/R1 + VT/R2 + VT/R3 + … + VT/Rn)
1/RT = 1/R1 + 1/R2 + 1/R3 + … + 1/Rn
Wednesday, February 9, 2011
Favourite Roller Coaster Design
Although I've been to a couple of amusement parks in my lifetime, the only one that I've been to recently and clearly remember is Canada's Wonderland. In terms of thrill, I'd have to go with Behemoth as my favourite roller coaster there, but I must give an honourable mention to Psyclone for it's ability to make me smile and laugh so widely that my saliva manages to escape my mouth. Yes, it is slightly, if not entirely, disgusting but I can't help it. However, in terms of design, I'd have to go with Wild Beast or Flight Deck.
No, there's nothing cool about Wild Beast besides the fact that it is made out of wood. It's just attractive to the eye in my opinion, but when you ride Wild Beast, I must say... it's not a pleasant feeling. It is extremely bumpy and you will feel nauseous (at least I do) and your head will hurt from the shakiness.
Flight Deck is another design I like simply because it has many curves and bumps and a loop or two (oh, and your feet get to hang during the ride). My descriptions are sort of weak and pathetic because I'm not exactly a roller coaster fanatic and I can't seem to think of descriptive adjectives, but I do enjoy riding them.
Here are some pictures of the roller coasters mentioned:
Behemoth
Psyclone
Wild Beast
Flight Deck
No, there's nothing cool about Wild Beast besides the fact that it is made out of wood. It's just attractive to the eye in my opinion, but when you ride Wild Beast, I must say... it's not a pleasant feeling. It is extremely bumpy and you will feel nauseous (at least I do) and your head will hurt from the shakiness.
Flight Deck is another design I like simply because it has many curves and bumps and a loop or two (oh, and your feet get to hang during the ride). My descriptions are sort of weak and pathetic because I'm not exactly a roller coaster fanatic and I can't seem to think of descriptive adjectives, but I do enjoy riding them.
Here are some pictures of the roller coasters mentioned:
Behemoth
Psyclone
Wild Beast
Flight Deck
Tuesday, February 8, 2011
From Battery to Circuit (Energy Transformation)
Currents have a continuous flow of charged particles moving through loads/resistors, conductors, and energy sources, but how in the world do the charged particles manage to continuously "jump" from the negative to the positive electrodes ("a conductor used to make electrical contact with some part of a circuit")?
The reason for this occurence is because there is an energy source, for example a battery, where chemical energy is produced. The battery continuously gives off these charged particles in order for the circuit to function but when battery "dies," it simply means that the reactants have been used up, therefore there is no more chemical energy to provide the charged particles into the circuit.
important terms: direct current (DC) and alternating current (AC)
question/comment/food for thought: I'm sort of confused with "conventional current" and "electron flow," and the textbook does not make it better because it keeps mixing the two terms together saying that current = electron flow. Not only that but conventional current is the movement from +ve to -ve... but what's moving if it's not the electrons!?!?!?!
The reason for this occurence is because there is an energy source, for example a battery, where chemical energy is produced. The battery continuously gives off these charged particles in order for the circuit to function but when battery "dies," it simply means that the reactants have been used up, therefore there is no more chemical energy to provide the charged particles into the circuit.
important terms: direct current (DC) and alternating current (AC)
question/comment/food for thought: I'm sort of confused with "conventional current" and "electron flow," and the textbook does not make it better because it keeps mixing the two terms together saying that current = electron flow. Not only that but conventional current is the movement from +ve to -ve... but what's moving if it's not the electrons!?!?!?!
Saturday, February 5, 2011
The Energy Ball
Looks can be deceiving as a simple, white ball that appears to be almost no different from a ping pong ball was, to my surprise, certainly more complicating than an air-filled, plastic ball. This ball is known as an energy ball and it demonstrates how a circuit works. This energy ball contains the batteries, as well as a flashing red light and a sound generator which produces a slightly irritating, one tone pitch. In order for this energy ball to function, it requires conductive matter or objects to close the circuit. Unexpectedly, just by touching one of the metal strips on the ball with one hand and the other metal strip with the opposite hand, it closed the circuit. Who would've thought that we would be able to conduct electricity and close the circuit? It was also possible to complete the circuit with other peers and even the whole class, as long as the circuit was closed by holding hands, or in our case, touching each other with our pinkies. Our group experimented with several other objects, using more than one energy ball, and different combinations of "circuit wiring." It was a fun and informational experience and a good opportunity to interact with other peers.
important terms: series and parallel circuits
question/comment/food for thought: In order for electrons to pass through the farther load (from the cell/battery/energy source) in a parallel circuit, it would take more time, right? I wonder... if the farther load was significanly distant (i.e.100 metres), would it be possible to see the difference of the further load lighting up slower than the closer one? Or would the speed still be undetectable to our eyes?
important terms: series and parallel circuits
question/comment/food for thought: In order for electrons to pass through the farther load (from the cell/battery/energy source) in a parallel circuit, it would take more time, right? I wonder... if the farther load was significanly distant (i.e.100 metres), would it be possible to see the difference of the further load lighting up slower than the closer one? Or would the speed still be undetectable to our eyes?
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