Cannons.

A cannon is defined as any piece of artillery that uses gunpowder or other explosive-based propellants to launch a projectile. They can be found in history as useful weapons many countries used during wars.

Cannons are generally prepared by placing gunpowder into the primer tube. The amount of powder would be adjusted depending on the distance of the target, the size of the cannon and the type of projectile being used.

A friction primer is used to ignite the gunpowder and is a hollow tube that fits into the vent hole. It has an opening that allows a serrated wire to be inserted inside. The wire has a loop on it where a piece of rope is attached and when it is time to fire, the rope on the friction primer is pulled. Then the serrated wire creates enough heat to ignite the gunpowder in the primer tube and ultimately create an explosion that would expel the projectile.

For furthur information on how a cannon works, check it out:
http://www.nps.gov/archive/fosu/2_History/how_cannon_works.pdf

Newton's Lab Results.

Through labour, Cindy, William, Richard and I managed to mangle these results out of the ticker-tape and pulley system.

Man, did we have fun measuring the distance between dots!

Our Newspaper Structure.

When given three sheets of newspaper and a desk-length of tape to work with, the quantity of materials seemed like a small one. We tested many different ways we could roll the sheets of newspaper to obtain the maximum length. We discovered that if we ripped the sheets into quarters, we could achieve a substantial amount of height for our tower which, after all, was the purpose. We decided that we would try and use a "cootie-catcher" base, where it would be inverted with a hole in the center so the  bottom of our thin, diagonally-rolled newspaper could be inserted and held upright. Turned out the newspaper was way too flimsy for the long structure for it to be the center of gravity and such a goal was unattainable. Before the real competition and measuring began, the sides of the cootie-catcher began to rip and the long 'tower' would no longer stay where we needed it to; off the floor. Our tower was not measured for, I guess we were technically disqualified when the cootie-catcher fell apart after our numerous attempts to make it sturdier. Charlie, Cindy and I arrived at the conclusion that the "hands-on" activities are not our forte. I fear for the outcome of our roller coaster.

Petronas Towers.

When asked to think about tall buildings, I thought about the Petronas Towers located in Kuala Lumpur, Malaysia. The Petronas Towers were the tallest buildings in the world from 1998-2004 at 452m until Taipei 101 was completed. Petronas Towers include 88 floors, constructed largely of reinforced concrete, and a steel and glass facade designed to resemble motifs found in Islamic art as a reflection of Malaysia's Muslim religion. They will retain the title of "world's tallest twin towers" and include unique features such as the sky bridge which connect the two towers together.

For the newspaper-tower building activity, a strong base seems to be the necessity. With a strong base, the upper, longer part could have the proper support to hold it up. Somewhat like the woman's center of gravity and the standing of the egg, we would want it lower and close to the ground so that it could stand upright without much assistance. Given that the sheets of newspaper are going to be limited, this would be the best type of structure we could make, while making the most out of the sheets.

Projectile Motion Worksheet Answers.

There was only two cases from what I could tell...

Gliding Egg Landers.

In French class, a couple of weeks ago, we had read about people who go hang gliding for recreational purposes. When Mr. Chung mentioned making an egg glide, my mind immediately backtracked to that class. When I pitched the idea to Cindy and Stephen, we had all agreed that for the time being, it seemed like the best idea.

Given that each group only gets 25 straws, a sheet of newspaper and a limited amount of tape, we'd have to build a structure that wouldn't be too big, but one that would be able to keep our egg from cracking. A hang glider model would be perfect for this assignment because it does not require a complex structure, nor an engine.

We could build a tringular shaped 'wing' which would provide us with the gliding element, and provide a structure we could attatch our egg from.

Taking into consideration that a chicken egg is hefty in weight, in comparison to the straws, that will most likely be a problem we'll have to work through as a group.

Till Wednesday, gliding egg lander.

Homework Check (pg. 72).

Homework questions from textbook page 72 #54, 56, 58, 60, 62 and 63.

Questions #54, 56,58,60,62

  

Question #63

'Walking the Graphs' Lab Results.

Distance-Time Graph - 01b

Velocity-Time Graph - 01b

Acceleration-Time Graph - 01b

Distance-Time Graph - 01c

Velocity-Time Graph - 01c

Acceleration-Time Graph - 01c

Velocity-Time Graph - 01d

Position-Time Graph - 01d

Acceleration-Time Graph - 01d

Velocity-Time Graph -01e

Position-Time Graph - 01e

Acceleration-Time Graph -01e

Position-Time Graph - 01f

Velocity-Time Graph - 01f

Acceleration-Time Graph - 01f

Velocity and Time Lab Activity.

On March 8, 2011, we did our first lab activity in class. The lab involved velocity/time, and distance/time graphs which we had to try and match through a motion detector. The first graphs we tried were distance/time graphs and after a couple of tries, our graphs started look like the graphs given. For a positive slope, we walked away from the motion detector, and for a negative slope, we simply walked towards the detector or simply stayed in the same spot for the horizontal lines. After conquering graphs B and C, we came to graph D which was our first graph for velocity/time. The velocity/time graphs, which is pertaining to speed, were a lot harder to match. They required geisha-like steps at a certain speed, closer or farther away from the motion detector and without a doubt, there were many trial and errors. This being said, the velocity/time graphs were a lot harder to try and correspond with.

Who can walk like a geisha at a constant speed for so long?

Distance/Time Graph - 01F

Right Hand Rule.

To execute the right hand rule, all you need is your right hand, and your voice - so you can meow.

Right Hand Rule #1 (for conductors):

Take your right hand, and point the thumb in the direction of the current (I) flow. The current will be travelling in a conventional current, meaning from positive to negative. Now meow and curl your fist. The direction of the fingers is the direction of the magnetic field (B) around the conductor, as seen in the diagram below.

Right Hand Rule #2 (for coils):

Once again, take your right hand, meow, then grasp the coil so that the fingers are curved in the direction of the current (I). The thumb points in the direction of the magnetic field within the coil and represents the north (N) end of the electromagnet produced by the coil. Take a look at the diagram below!

Concept Maps.

After spending majority of our physics class cutting, gluing, and scribbling our thoughts down on a piece of paper, our group somehow managed to end up with a decent looking concept map. Sure, Dennis’ handwriting looks like chicken-scratch and it isn’t laid out in an artistic fashion, but as a group, we felt that it was easy to follow and accurate. What else do you really need from a concept map?

Here are TEN things I learned from this assignment:

1) electron flow is from negative to positive charge, while a conventional flow is positive to negative charge.

2) Ohm's law states that current (I) is directly related to voltage (V) and inversely related to resistance. (R)

3) equation for current is I = Q/t, where I represents current, Q is the charge in C, and t is for time in seconds.  

4) in series circuits, charge flows along one path, and in parallel circuits, charge flows along two or more paths.

5) Kirchhoff's laws are a current law, which states that the total current flowing into a connection equals to the total current flowing out of a connection. Kirchhoff's laws are also a voltage law, which states that the algebraic sum of the potential differences around a closed pathway equal to zero.

6) electric charge is measured in coulombs, where 1C = 6.24 x 10^18 elementary charge (e), and 1e = 1.60 x 10^-19 C.

7) electric current is defined as rate of flow, of charge, past a point and is measured using an ammeter, connected in series. Electric current is measured in coulombs per second, which equals amperes, which can be written in the equation, I = Q/∆T. I represents electric current, Q is the quantity of charge and ∆T is elapsed time.

8) electric charge is represented in the equation Q= Ne, where Q is the quantity of charge, N is the number of elementary charges and e is the number of coulombs per elementary charge.

9) potential difference is can be calculated by E/Q, where V is represents potential difference/voltage in volts, E stands for energy or work in joules, and Q is the charge in coulombs.

10) power can be represented by P = IV, P = V²/R and P = I²R where P is power, I is current, V is voltage and R is resistance.  

Knowing all this information makes me want to fist pump.

Ohm and Kirchhoff.

Ohm's law states that current (I) is inversely related to resistance (R) and directly proportional to voltage (V).

"The amount of current flowing through a resistor varies directly as the amount of potential difference applied across the resistor as long as other variables, such as temperature are controlled. There is a resistance of 1 Ω when 1 A of current flows with a potential difference of 1 v across a resistor." - Physics: Concepts and Connections.

Gustav Kirchhoff's research led to the publication of his laws in regards to current, voltage and resistance.

In series circuits,

In parallel circuits,

Kumba.

When I was a little girl, I used to have the fear of falling out of roller coasters and dying, so I’ve always opted for rides like the spinning teacup. However, growing up with an older brother who didn't really give me a choice when we went to amusement parks, I quickly learned that adrenaline rushes were not so bad after all. To this day, a little part of me still has the fear of falling out and would rather stay away from the ones that drop from tremendous heights, and go for the shorter ones with multiple sets of loops. Kumba, a steel-twister coaster, was the first ride to feature interlocking corkscrews and a diving loop from the Bolliger & Mabillard Consulting Engineers Inc., and can be found in Busch Gardens, Tampa Bay. Kumba is 44 m tall, 1212 m in length, 7 inversions and a maximum speed of 97 km/h. Within the 2:54 minutes of this ride, the roller coaster will go through a 35 m vertical loop, Zero-G and cobra roll, as well as 2 interlocking corkscrews. 

If I had to fall and die from any ride, this would definitely be my choice.

For additional information and videos, check out the website below! http://www.buschgardens.com/bgt/Explore/Rides.aspx?id=594

Batteries to Circuits.

A source of electricity, such as a battery or a generator is used to create chemical energy. The chemical energy produced is used to create voltage (electric potential difference) between the battery and the electrode. The movement of charge from a negative to positive charge, known as a electron flow, occurs in this process. The product of this process is electrical energy, which will then be converted into different forms of energy. This process gets repeated continuously for the same results, which in this case would be to light the lightbulb, as shown on the diagram above.

The Energy Ball Activity.

Just as I was about to crack a joke about how we should all whip out our ping-pong paddles, the ping-pong ball look-a-like began to emit an irking sound. Little did we know, the white ball contained a circuit system, batteries, a sound generator and a small, red light bulb. When a conductor (ex, hands, metal tip of scissors, etc.) touched both of the metal strips on the ball, a one-pitch sound was emitted, along with a bright, red light.

After tossing around some ideas within our small groups, the whole class was given a challenge. If we were able to complete the challenge, our prize would be going to the "A.Y. Jackson Multicultural Lunar Festival." As Mr. Chung caught onto the looks we were throwing at each other, he quickly amended that we would go regardless of the situation. What a loss.

Within a big circle, we quickly discovered the meaning of a series circuit; if any one of us were to stop touching pinkies, the circuit would break, and the balls would no longer make the sound and light up. When we put a line of students in the middle of our circle, and depending on who stopped touching each other, we discovered the meaning of parallel circuits. I felt a sense of accomplishment and power that out physics class could control which ball reacted, and which didn't.

I really appreciated that we didn't have to learn this out of the textbook, but rather by having an in-class activity. This experiment was an ample way to start our semester together.