Types of Energy (Blog 18)

Energy is everywhere; some types can be seen and some cannot. Below are some types of the wide array of energy forms.


Thermal Energy
Thermal energy is caused by the increased activity of molecules in any given substance. This process increases the temperature, causing it to rise and be warmer. Subsequently, lower activity or velocity of molecules would make the temperature fall. Thermal energy relies on the laws of thermodynamics, which states that energy in the form of heat can be exchanged from any given object to another object. 



Chemical Energy
Chemical energy is also based off of the laws of thermodynamics. With these laws, complicated equations that can be used to figure out chemical energy can be utilized. It is found in food, and energy is stored in the molecular bonds of the food. Thus, it is also a form of potential energy. By the process of respiration, the molecules are broken down and used by various cells of the body.


Electrical Energy
Electrical energy is the flow of electric charge. Examples of electrical energy in action would be energy found in electromagnetic fields and lightning. We have found ways to store this type of energy to further use it for other purposes. Electrical energy can also be generated by burning fossil fuels, which is a popular but non-environmentally friendly way of producing energy.


Sound Energy
Sound energy is probably the most interesting form of energy for me since I'm interested in music. It relies on sound vibrations that travel through a material to produce sound. It depends on the material on what kind of sound it makes. Sound energy is essentially mechanical energy but is not used for energy usages for humans because the amount of energy it produces is rather small.



Other forms of energy include elastic energy, magnetic energy, nuclear energy, and radiant energy.

Howitzer! (Blog 17)

Cannons are used as artillery weapons which require gunpowder to launch a projectile. Each cannon can be different, with different range, angle of fire, calibre, rate of fire, and firepower. It can vary depending on what is required during a battle.


In order to find out how to maximize the range of the projectile shot out of the cannon, the angle that the cannon should be placed along with the horizontal is 45 degrees. This is in between 0 and 90 degrees, and is rightly so because if it is any higher, the projectile would be fired upward too much, causing a loss in distance. Conversely, the degree cannot be under 45 either because the projectile will not reach its maximum potential velocity - also losing some distance. The formula  R = V²sin(2θ)/g can be used to determine the maximum x-distance.


The longest-range projectile fired out of a cannon would be the Paris Gun, used in WWI in 1918. It was used by Germany to bombard Paris but wasn't very successful. It was not meant to destroy the city, but was actually meant to reduce the morale of the citizens there, making them afraid.

Dynamics and Newton's Laws (Blog 16)

Dynamics
Newton's three laws of motion:
1. Inertia --> objects will continue to be stationary or in motion unless an external force is affecting it
2. F = ma --> force is directly related to acceleration and thus mass is indirectly related to acceleration
3. For every force, there is an equal force going in the opposite direction.


Thus, there are four applications from Newton's laws. They are equilibrium, inclines, pulleys, and trains.
Equilibrium
- occurs when the object is not moving at all
Assumptions:
- no friction
- a = 0 (and therefore ax and ay are also 0)
Inclines
Static:
- occurs when the object is not moving while it is on a slanted base
Assumptions:
- no acceleration
- positive axes in the direction of motion
- no air resistance
- μ = tanΘ
- static friction = coefficient of static friction times normal force
Kinetic:
- occurs when the object is sliding down a slope
Assumptions:
- positive axes in direction of motion
- normal force is perpendicular to surface
- no air resistance
- ax ≠ 0, ay = 0
- kinetic friction = coefficient of kinetic friction times normal force
Pulleys
- occurs when objects are at a distance from each other separated by a wheel held by ropes
Assumptions:
- frictionless pulleys + rope
- no air resistance
- multiple free body diagrams
- positive axes in direction of motion
- T1 = T2
- acceleration of system is the same
Trains
- occurs when one uses common sense to figure out what a train is
Assumptions:
- 1 FBD for acceleration
- 3 FBDs for T1 & T2
- ay = 0
- a is consistent
- no air resistance
- weightless cables
- positive axes in direction of motion


All four applications may be used to figure out the calculations for tension, force, mass, and acceleration. 

Projectile Motion (Blog 15)

In order to calculate the speed, time, and distance of an object that is thrust into the air and back down, one must take into account where the object started and where it landed. It should fit into one of the four lines in the following diagram.

The black line is when an object is pushed straight forward into the air. It will go downward because of the force of gravity pushing it down. If there was no gravity, the object will continue going forward without going down.

The red line is when an object is thrown directly into the air at a certain angle and going back down to where it started, except with a significant distance from the starting position.

The blue line is when an object is thrown into the air but it does not land on the same level as when it was thrown. It lands at a level above the starting position.

The green line is the same as the blue line, except the level is below the starting position.

By using the x and y components and the big five equations, one can determine many useful information about the particular object being thrown.

My Favourite Roller Coaster (Blog 14)

This blog post has got to be the best homework assignment I've ever had in my school life. Writing about my number one interest on a blog? That is amazing.

As a roller coaster enthusiast, I inevitably have tons of favourite roller coasters. However, I do have one certain coaster in mind that is my absolute favourite. It is the coaster in the image shown above - Raptor.

Raptor is a Bolliger & Mabillard (famous roller coaster manufacturer) inverted coaster located at Cedar Point, my favourite amusement park in the world, situated on an island on Lake Erie in Sandusky, Ohio, USA. It possesses a height of 140 feet and reaches a maximum speed of 57 mph, before going through a total of six inversions.

A photo I took of Raptor during my Cedar Point trip in the summer.

Why do I love this coaster so much? Back when I was in grade 4, I discovered Cedar Point, and I was awed by the quality and quantity of the coasters located there. A certain green coaster with bright pink trains enlightened my eyes, and my fascination with this coaster grew and grew. I researched about it until I had all its stats memorized by heart. I watched all the online videos for this coaster and I always recreated it on roller coaster simulators and games. It was my dream to ride Raptor in real life.

Alas, I was still in elementary school, and my dream of going to Cedar Point and riding Raptor was very distant. However with every single year that passed, I would still ask my parents if we were ever going to Cedar Point. It was always a very iffy answer, and it never happened. But then came June of 2010, when my parents were deciding on vacation plans for the summer, I half-heartedly suggested "Cedar Point!" It was more of a joke to me because I knew it would never really happen. A miracle happened though - they said okay.

I was ecstatic for the next months and I could not really focus on anything else. The upcoming August month would consist of the days I'd be visiting and staying at the hotel at Cedar Point. I researched even more about Cedar Point, even though I already knew everything about it. I could not contain my excitement, and as each day went by, the more stoked I was.

The day finally came and we drove down to Ohio - a total of a 7 hour drive. As we reached the peninsula, I saw the skyline of Cedar Point. Within that, I also saw the outline of my favourite roller coaster in the world - Raptor. As we entered the park, I raced towards the entrance of Raptor. I was actually seeing it with my own eyes, in real life. It was towering over the midway of the park, and the screams of the guests riding it just increased my excitement even more. I went into the queue of the coaster, and after an hour and thirty minutes of waiting, it was at last my turn to go on the ride. I sat in the comfortable seat and readied myself for a hopefully great ride on Raptor.

After two minutes and fifteen seconds, I was back at the station. My reaction? It wasn't great at all...it was magnificently amazing. It was even better than I expected. Although it was built in 1994, it was still smoother than all of the rides I've ever gone on. It was probably the happiest moment of my life; I had rode on Raptor.

Below is a picture of me standing in front of Raptor's huge loop.

Best day of my life.

This is actually a condensed version of my original blog about Raptor. This (click) was my first entry, on my own personal blog. Just in case anyone thinks I'm plagiarizing from that site, I was the one that wrote it.

The Physics of Roller Coasters (Blog 13)

As someone who is clearly interested in roller coasters, it would be pretty embarrassing if I did not know how roller coasters worked. Using an example of a simple out-and-back coaster with no inversions, I will explain the physics of it.

Essentially, for a wooden or steel roller coaster that just has airtime hills, a train is carried up a lift chain and dropped down with gravity powering it. Two types of energy are significant in roller coasters - potential energy and kinetic energy. 

A roller coaster train has more potential energy as it goes higher above the ground. Basically, the higher the lift-hill, the more potential energy the roller coaster has. At the highest point of the coaster's lift, the maximum potential energy is reached. As the train drops from that height, gravity powers the train downward, gaining velocity. At this point, the potential energy is transferred into kinetic energy. Potential energy is regained on succeeding hills.


Kinetic energy is the energy of motion. On a roller coaster, it is determined by the train's motion and its mass. Gravity induces speed of the roller coaster train, thereby creating kinetic energy. Along with potential energy, kinetic energy is part of the total mechanical energy of the coaster. Potential energy transfers into kinetic energy, and that is the basis of what powers a roller coaster. 

Diamondback, a B&M hyper coaster, located at Kings' Island.

How to Add Vectors (Blog 12)

Steps on adding vectors:

1. Draw out the lines of direction.

2. Mark origin; draw "shortest distance" from origin to destination. (creating hypotenuse)

3. Define positive axes (N and E are positive, S and W are negative).

4. Group X and Y lines together; add X's together and Y's together.

5. Use Pythagorean theorem (c² = a² + b²) to determine the shortest distance's distance.

6. Use trigonometry to find the required angle.

Big Five Equations #4 (Blog 11)

How to derive equation number four from a graph.
Equation 4 is d = V2Δt - ½aΔt².

The area of the rectangle drawn on the graph is d = V2Δt.
The area of the triangle formed above the line V1 to V2 is d = ½ (V2 - V1) (Δt).
Therefore, the displacement equals the area of the rectangle minus the area of the triangle.
d = V2Δt - ½ (V2 - V1) (Δt).
From equation 1 (from the big five), V2 - V1 = aΔt.
Sub equation 1 into displacement equation:
d = V2Δt - ½ (aΔt) (Δt)
d = V2Δt - ½aΔt²

Big Five Equations #3 (Blog 10)

How to derive equation number three from a graph.
Equation 3 is d = V1Δt + ½aΔt².

The area of the (A) rectangle is d = V1Δt.
The area of the (B) triangle is d = ½ (V2 - V1) (Δt).

Therefore, the displacement is equal to the area of the area of the (A) rectangle plus the (B) triangle.
From the big five's equation 1, V2 - V1 = aΔt
Sub equation 1 into the displacement equation.
d = V1Δt + ½ (aΔt) (Δt)
d = V1Δt + ½aΔt

Walking the Graphs (Blog 9)

Last week we did an interesting lab. We had to actually exercise! ...although not much. Nevertheless, it was a great experience working on a lab which involved us trying to follow the lines on the graph by running, walking, and stopping.

1. Stay for a distance of 1m for 1 second.

2. Walk 1.5m in 2 seconds (0.75 m/s) away from the origin.

3. Stay at a distance of 2.5m for 3 seconds.

4. Walk 0.75m in 1.5 seconds (0.5 m/s) towards the origin.

5. Stay at a distance of 1.75m for 2.5 s.

1. Start at a distance of 3m from the origin. Walk back towards the origin 1.5m in 3 seconds (0.5 m/s).

2. Stay at a distance of 1.5m for 1 second.

3. Run towards the origin 1m in 1 second (1 m/s).

4. Stay at a distance of 0.5m for 2 seconds.

5. Run away from the origin 2.5m in 3 seconds (0.83 m/s).

1. Stay still for 2 seconds.

2. Walk away from the origin at 0.5 m/s for 3 seconds.

3. Stay still for 2 seconds.

4. Walk towards the origin at 0.5 m/s for 3 seconds.

1. Slowly accelerate away from the origin to 0.5 m/s in 4 seconds.

2. Continue walking away from the origin at 0.5 m/s for 2 seconds.

3. Turn around and walk towards the origin at 0.4 m/s for 3 seconds.

4. Stop and stay still for 1 second.

1. Start at a distance of 0.8m from the origin and walk away 1m in 3.5 seconds (0.29 m/s).

2. Stay at a distance of 1.8m for 3.25 seconds.

3. Continue walking away from the origin for 1.4m in 2.25 seconds (0.62 m/s).

1. Walk away from the origin at 0.35 m/s for 3 seconds.

2. Walk towards the origin at 0.35 m/s for 3.5 seconds.

3. Stand still at that position for 3.5 seconds.

Building a Motor (Blog 8)

Looking at those real-life engines of automobiles and technological devices and machines amazes me. One thing that runs them is the motor. Today we created this very motor - albeit a very amateur version of it. However it was still quite an experience.
The tools and materials we used for our endeavour:

• piece of wood
• wine bottle cork
• skewer
• Lego pieces (in replacement of paperclips)
• wires
• pop can
• nails
• tape, hammer, sandpaper, thumbtacks

Before the insertion of the cork.

The first thing we did was measure the distances between the four nails to make sure they were in the right position. After we hammered the nails into their positions and placed the makeshift paperclips (Lego pieces) in its proper positions. Getting the skewer to go through the cork proved to be a difficult task. We came up with the conclusion of hammering a nail inside the middle of the cork to make the hole more easily accessible. After some necessary force, we finally got the skewer in through the cork. It was pretty straightforward after this step. 

Before the insertion of the brushes.

We put the brushes (pieces out of a V8 can) into its positions and with a little bit of adjustments we were able to complete the project. The only thing left to do was test our "motor" to see if it worked. We went up to the front to get our motor tested.

As you can see from the video, our motor was successful - we were the fifth group to complete the task. Our final product looked like this:

In retrospect, it was a rather fun activity - it was both fun and educational at the same time. Those kinds of activities seldom come, so it will probably be one of the more memorable in-class school projects this year.

Right Hand Rules (Blog 7)

Today we learned about two important components of magnetism in class: right-hand rule #1 and right-hand rule #2.
Firstly, Oersted's Principle states that electric charge moving through a conductor creates a circular magnetic field around the object. Thus, right hand rules are used to determine the magnetic forces around an object.

Right-Hand Rule #1:
Grasp the object (conductor) and make sure your thumb is pointing in the direction of the current direction (conventional flow). Curve your fingers inwards and that will tell you the direction of the magnetic field.


Right-Hand Rule #2:
Grasp the object with curved fingers in the direction of the flow. The thumb represents the North direction.

Notes on Magnetism (Blog 6)

page 582 - 589


Several points on our new unit, magnetism:

• a magnetic field is the distribution of a magnetic force in the area of a magnet
• two different characteristics of magnetics: north and south --> responsible for magnetic forces
• north and north (thus, south and south too) magnetic poles repel one another while the opposite poles attract
• a test compass is a tool to map a magnetic field
• the Earth is similar to a magnet, since it produces its own magnetic field
• ferromagnetic metals are metals that are not magnetic, but attract; ex. iron, nickel, and cobalt
• the Domain Theory of Magnets: all large magnets are made up of many smaller and rotatable magnets, called dipoles, which can interact with other dipoles close by; if dipoles line up, a small magnetic domain is produced
• Oersted's Principle: charge moving through a conductor produces a circular magnetic field around the conductor



RHR #1

• right-hand rules: hand signs to help predict how magnetic forces act
• right-hand rule #1 (RHR#1) for conventional current flow: grasp the conductor with the thumb of the right hand pointing in the direction of conventional (positive) current flow; the curved fingers point in the direction of the magnetic field around the conductor 



RHR #2

• right-hand rule #2 (RHR#2) for conventional current flow: grasp the coiled conductor with the right hand such that curved fingers point in the direction of conventional current flow; outside the coil, the thumb represents the northern end of the electromagnet produced by the coil 
• factors that affect a magnet's strength: current in the coil, number of turns in the coil, type of material in the coil's centre, and the size of the coil

Notes on Resistance (Blog 5)

September 14, 2010
pages 553-563


Some points I found useful during my reading:

Ohm, a very handsome man

• the amount of energy (current flow) in a circuit that is transferred to a device relies on the potential difference of the power supply and the nature of the path through the electric potential energy-using loads
• the more difficult the path in a circuit, the more opposition there is to flow - called resistance
• resistance is measured in ohms (Ω); named after Georg Simon Ohm, a German physicist 
• the formula for resistance is R = V / I; V is the potential difference and I is the current
• Ohm's law: the V / I ratio is constant for a certain resistor; in order to prove Ohm's law, you will need to measure data, plot the data, find the slope, and then create an equation
• factors that determine resistance depend on the properties of the conductors; the length, cross-sectional area, the material, and the temperature of a conductor affect resistance (eg. thin wire has a large resistance compared to a thick wire)
• the gauge number of a wire tells us its cross-sectional area; a small gauge number has a large cross-sectional area, and vice versa
• superconductivity: the ability of a material to conduct electricity without heat loss due to electrical resistance
• series and parallel circuits were studied by Gustav Robert Kirchhoff, a German physicist; his studies led to Kirchhoff's laws
• Kirchhoff's current law: the total amount of current into a junction point of a circuit = the total current that flows out of that same junction



The resistance formula triangle.

• Kirchhoff's voltage law: the total of all electrical potential decreases in any complete circuit loop is equal to any potential increases in that circuit loop

Ohm's Law: Reference Chart (Blog 4)

The Energy Ball (Blog 3)

September 10th, 2010

Our class received two objects: an envelope full of smiley faces with questions written on them and an "energy ball," which was apparently an extremely expensive ping pong ball. The twelve questions were to be answered; to the best of my ability I have done so:

1. Can you make the energy ball work? What do you think makes the ball flash and hum?

The energy ball works when I touch both metal contacts with my fingers. This is because my body is a conductor of electricity, with all its charged ions inside. As both contacts are touched, I complete the circuit, making the ball flash with noises.

2. Why do you have to touch both metal contacts to make the ball work?

If I do not touch both metal contacts, I will not complete the circuit, and therefore the electricity will not pass through and go back to its power source. Without a complete circuit, the ball will not light up.

3. Will the ball light up if you connect the contacts with any material?

The material that you use to connect the metal contacts is the vital source of whether or not the ball will light up. The material definitely cannot be insulators such as rubber, plastic, or glass, as they do not conduct electricity. If they do not conduct electricity, the circuit is not complete and thus the ball will not light up.

4. Which materials will make the energy ball work?

Most types of metal such as silver, copper, nickel, and gold will conduct electricity and therefore make the energy ball work. 

5. This ball does not work on certain individuals - what could cause this to happen?

This was a puzzling question at first, but with further thinking, answers came upon me. I believe if someone's skin is extremely dry, it will not conduct electricity. The contact point of the metal contact and the person's finger will not transfer any electrons because of the dry nature of the finger. Without the transferring, the circuit will not be complete and the ball will not work.

6. Can you make the energy ball work with all 5-6 individuals in your group? Will it work with the entire class?
Yes, if every member in our group has physical contact with each other's skin, and each metal contact on the ball is touched by a different person, the ball will light up. It worked with the entire class as well since it is the same circuit, except bigger or longer. Fortunately no one in our class proves question number five correct, and the electricity is transferred through every individual.

7. What kind of circuit can you form with one energy ball?
With one energy ball, a simple circuit can be formed. It can have an open/closed switch when I put my finger on the contact point.

8. Given 2 balls: Can you create a circuit where both balls light up?
Two energy balls can definitely simultaneously light up. By using at least two people (although difficult, one person could be possible too), two balls can light up if each contact point is touched with any finger. As long as each contact point is touched, the circuit is complete and both balls light up.

9. What do you think will happen if one person lets go of the other person's hand and why?
If one person lets go of the other person's hand (or pinky in this case), the circuit will not be complete and the flow of electrons will not carry on. Thus, the energy ball will evidently not light up.

10. Does it matter who lets go?
No, it doesn't matter who lets go because as long as one connection is lost, the circuit will not be complete.

11. Can you create a circuit where only one ball lights (both balls must be inclined in the circuit)?
Yes, a parallel circuit must be made for this to occur. One circuit will be running continuously as the other one opens and closes. With this happening, one ball will be lit while the other will be off, even with both inclined in the circuit.

12. What is the minimum number of people required to complete this?
In class, the minimum number of people that tried it was six people, but it would probably work with less than four people, as long as they are all capable and cooperative.

Parallel and Series Circuits
As talked about above, parallel circuits are basically two simple circuits side by side. Both circuits share one "line" of wire, so to speak. Staying true to its name, parallel circuits have their loads and resistors placed parallel to each other in the circuit, as seen in the diagram to the left.


Series circuits are basically a series of simple circuits whose loads and resistors are connected one after another in one direction.

The difference between series and parallel circuits.

Tall Structures (Blog 2)

Challenge
     Yesterday during class we underwent our first challenge - to build the tallest newspaper structure in the class. Upon hearing it, it did not seem like a difficult task to conquer. However, I was proven blatantly wrong.
     In groups of three or four, our class had twenty minutes to attempt our first shots at architecture and engineering with five pieces of newspapers and a limited supply of masking tape. The first and overall mistake we made was not planning our structure well enough. Although we did talk about how we were going to shape the newspaper, the time we took for that was far too short and we should have allotted some more time for the planning portion of the challenge.
     The reason our structure was unsuccessful in terms of physics was because the foundation did not have enough support and the weight distribution were in the wrong areas. We should have applied more newspaper to the base of the structure so it could hold up the remaining newspaper and tape. As we sadly figured out, the structure kept falling over because of the weak base despite the amount of changes we made to it. In the end our structure measured about 20 centimetres while the winning structure measured around 185 cm. Although our newspaper structure lacked in height, we were not in last place and we had fun making it.

My group members holding up what our structure would have looked like if it had been stable.

Tall Structures
     Tall structures obviously wouldn't be as stable as smaller, shorter structures if they were built the exact same way - they would topple over and be demolished in seconds. Therefore, we would need to figure out what exactly makes a tall structure stand still.
     First of all, there should be a low centre of gravity so most of the weight is distributed on the bottom. That would mean the top would not fall over (that easily). Secondly, the foundation or the base of the structure should ideally be as large as possible to insure its stability. As each story on a building progresses, it can become gradually slimmer - but always make sure the base is thick and strong.
     Another characteristic to make a structure more stable would be to use triangles, as they are the strongest shape. They either expand or contract, so they will not bend and break. 

The Eiffel Tower uses the idea of building from a large base to a slim top.

Top Thrill Dragster - 420 ft, 120 mph

     The above roller coaster broke records in 2003 when it was unveiled for both height and speed. It has now been surpassed by a similar coaster, but it still remains second. How could such a tall roller coaster be standing without toppling over? As you can see, the yellow supports adjacent to the track hold it up, and the shape the supports form are triangles. This utilizes the effect of how triangles are the sturdiest shape.

The Centre of Gravity

     The centre of gravity is the point around which a body's weight is equally balanced in all directions. It keeps an object balanced and stable. Symmetry is important when it comes to the centre of gravity and stability. If an object is toppled to the side a bit, the centre of gravity will shift  to make sure the mass is evenly distributed throughout the object, but inevitably it will topple over.

Notes on Current Electricity (Blog 1)

Wednesday, September 8, 2010
Physics textbook: pages 544-552

• a flow of electrons is called an electric current
• a current, much like a water current, flows from a positive terminal to a negative terminal
• equation for a current: I = Q/t, where I represents current in amperes, Q represents the quantity of the current, t represents time in seconds
• an ammeter is used to measure currents of two types: direct current (DC) and alternating current (AC)
• DC: the current flows in one direction from a power supply (ex. battery) to the load (ex. lightbulb), then back to the power supply
• AC: the current has electrons that reverse because of electric and magnetic fields; the path of the current is also known as a circuit

• the equation to show the electric potential difference used is V = E/Q; V is the electric potential difference in volts, E is energy in joules, and Q is the charge in coulombs
• the equation E = Vlt calculates the energy transferred by charge flow
• a voltmeter is used to measure potential difference
• throughout the world, there are many different ways to convert energy from chemical, mechanical, thermal, and light to electric potential energy; wind, coal, oil, nuclear plants, and solar energy, among many examples, may be used