Category Archives: Physics

One World: Think Global, Acting Local; PET Bottles

PET bottles, are dependently used in Canadian Academy, in Japan, and in almost every single country in the whole world. “PET stand for polyethylene terephthalate, a plastic resin and a form of polyester. Polyethylene terephthalate is a polymer that is formed by combining two monomers: modified ethylene glycol and purified terephthalic acid” (National Association for PET Container Resources, 2009). PET is the most commonly used packaging material, and is used in a various amount of packaging, from product to cosmetics.

Canadian Academy’s cafeteria company, Cezar’s kitchen orders an estimate of 2500-3000 PET bottles a month, just for our schools community to use. And the vending machines installed in Canadian Academy has around 750-800 PET bottles a month. This adds up to 3800 PET bottles in total, and we have around 6 months of school. So the grand total of how many PET bottles the Canadian Academy community uses, solely on campus, is around 22,800 PET bottles. This number discludes the other purchases by students and faculty outside of campus. This number needs to change. This number needs to decrease.

PET bottles have a great negative impact on the environment. PET bottles and other un-eco-friendly substances are one of the largest factors of global warming. Air pollution is caused by the manufacturing plants when PET bottles are being manufactured and also, when the PET bottles are being carbonized, toxic chemicals and other substances/pollutants and released. Chemicals released can lead product and water to be infected. Product and water can not only be affected by the air pollution, but also by direct contact. The number of bottles that are not recycles, are dumped and found in the ground. The soil and dirt, getting contaminated by the toxins released, cannot let the product grow and flourish to it’s full potential. Furthermore, the transportation of all the PET bottles causes pollution. Bottles are usually shipped, or transported by train. Shipping takes a lot of energy, and trains operate on burning oil & using gasoline in trucks. Fossil fuel consumption is effected by PET bottles, too. Crude oil, natural gas and ethylene glycol are only some of the materials/chemicals/substances used to create bottles. “In fact, according to Enso Bottles, “the production of 1 kg of PET, requires the equivalent of 2 kg of oil for energy and raw material.” And according to Green Upgrader, it takes approximately 24 million gallons of oil to create about one billion plastic bottles, and the average American consumes 167 bottles of water every year” (McQuade). There is also an excess amount garbage not being recycled and being thrown away and kept in at a shore, in the ground, or garbage dumps. “When incinerated, plastic becomes toxic; when buried, it may take 1,000 years to biodegrade. Plastic bottles also make up a large part of the what is known as the Great Pacific Garbage Patch” (Klein).

PET bottles not only have a great negative impact on the environment, but on the human body, too. People say to reuse PET bottles, believing it would be eco-friendly. Even though it maybe be eco-friendly, reusing PET bottles is very harmful to our health. Because PET bottles have a  unique structure and are tough to clean, microbial contamination may be posed. “Rocky Anderson, the mayor of Salt Lake City and a critic of bottled waters, pointed out environmental and economic concerns with bottled water and then added, “[A]nother problem, by the way, [is that] disposable plastic water bottles can contain antimony, which is a potentially toxic trace element with chemical properties similar to arsenic.””(Voiland, 2007). Scientists have also discovered that the bottles leak hormone-disrupting chemicals into the fluid. “”What we found was really surprising to us,” Wagner said. “If you drink water from plastic bottles, you have a high probability of drinking estrogenic compounds.””(Sohn, 2009). “””This is coming at a good time because the use of bottles for consuming water is getting very bad press now because of its carbon footprint,” she said. “It’s just another nail in the coffin of bottled water, the way I see it.”” (Sohn, 2009). In some bottles, BPA is used in the plastic. The leak of BPA is the water can lead to complications in the fetus and the pregnancy. A various amount of chemicals are used in PET bottles, each of them having negative affects on the human beings body and health.

In the year 2004, the United States consumed 28,000,000,000 bottles in one year, and 86% percent of that became garbage, not being recycled. This beens every second 1,500 bottles became garbage. Those 28,000,000,000 bottles needed 17,000,000 barrels of oil to be made. Those many bottles added an extra amount of 2,500,000 tons of carbon dioxide. This costed $100,000,000,000 dollars.

If we do not make a change now, there will be no space left to put garbage, the fossil fuel emissions will not decrease, but stay constant and even increase. Harmful chemicals and toxins will continuously be released into the air. This is important for me because I have to think about my life ahead, my health. I have to think about my children, their lives and health, and the generations going to come. I don’t want my generation to be responsible for possibly ruining the whole world. This issue effects mine life, your life, my and your families & friends life. It effects the people that don’t even use PET bottles. All of us need to change our ways, reduce, reuse, and recycle, and it all has to start with us, at Canadian Academy. Thinking global, acting local.

Our group conducted a survey questioning each students (in the high school’s) habits and knowledge. We asked a various amount of questions, but felt the data below is the more valuable.

From the data above, it is fairly straight-forward to conclude that the high schoolers attending CA are not fully educated about PET bottles and their effects on us. Also, every 5 out of 9 high schoolers do not bring their own water bottle from their house.   We also interviewed Mrs. Nishizawa, a faculty member that runs Eco Club in the middle school. In the 2010-2011 school years, 1,497kilograms of PET bottles have been recycled. This is a extremely huge number for a school with a population of less than 850. A while ago, CA would have to pay to pick up company to come and collect the garbage, which included PET bottles, since not considered it’s a house, but a business. But, through Eco Club creation, a contract with Environmental Office of Kobe City was made, and it’s goal was to encourage children to recycle. This is the prime reason there is an Eco Club currently. Through this club, Kobe City sends a private pick up truck, and CA does not have to pay for this service. CA is paid 3 yen per kilo of PET bottles and aluminum cans. The intention of Kobe City is to get people to recycle, instead of throwing it away. Money is a good way to motivate people.

Recycling is not the ideal solution for Canadian Academy at the moment. Even though recycling is a step towards success and improvement, it does not have a good effect on the environment. The way PET bottles are recycled is the process of burning the mountain of bottles, and this releases a massive amount of CO2. It is extremely unhygienic for people living near those sites, the workers, and once the air flows, everyone is basically breathing contaminated air. Most of the processed PET bottles aren’t reused since they aren’t durable for any other manufacturing. People are manipulated and are told that recycling is actually a good thing, and we are helping the environment, (of course it’s better than landfills), but we aren’t actually helping. We need to take a step further. What CA has to do is:
1.) eradicate and completely ban every student, faculty and staff member from having PET bottles
2.) somehow get rid of the vending machines
3.) educate all students about the environmental & health affects
– water in Japan is SAFE
– 90% of the price of PET bottles if solely for the bottle
4.) have a all-school-day juice/soda bar where students can pay once a day for unlimited refills —- using their own bottles from their home —– not plastic. CA or the high school student body council could hand out complementary water bottles that can last efficiently.

The solution to this issue definitely has advantages and disadvantages. First, the PET bottle consumption will go from 1,400+ kilograms straight down to 0 kilograms. This is the biggest advantage and goal, which it is very reachable. Looking at this system CA hypothetically has adopted, would allow other neighboring or international schools to innovate and make their school eco-friendly. Some disadvantages would be the extra dependency on Cezar’s Kitchen and CA to get the drinks and set up the system to be efficient. Water fountains have previously been installed all over the school, so that is not an issue. This solution may cost CA more money, but since most classrooms do not allow any drinks other than water, the demand for drinks other than water are unlikely to rise. Even though it may cost a slight bit extra, our school is accomplishing a huge goal, leaving impacts of Rokko Island, and even the Kobe City Environmental Office. In the long run, the money spent on this solution compared to the money spent for the vending machines and Cezar’s kitchens facility will be probably less than half. This solution will allow the students and faculty to drink better, healthier water, diminishing the risks of any toxins or chemicals to enter your body through PET bottles. This solution will allow the Eco-club to halt their work and concentration on recycling PET bottles, and will lead them to other ‘un-green’ activity happening in our school, such as the paper towel crisis. CA earning/saving money and their students being healthy is what will make this school a better place. This solution needs to be put to action as soon as possible, we cannot make the Earth wait any longer for a change. The Parent-Teacher Association, and the Cezar’s Kitchen business can put this to action, along the side of the high school student body council. It is a clear, easy vision, our school being absolutely free of plastic bottles, everyone taking care of their resources and their environment. Canadian Academy can act locally now, we are going to take it one step at a time.

Interesting Recommended Websites


Flint, D. (n.d.). Negative effects of plastic bottles on the environment. Retrieved from

McQuade, T. (n.d.). The effects of using PET bottles. Retrieved from

The safety of PET bottles. (2007, July 26). Retrieved from

Sohn, E. (n.d.). Plastic water bottles may pose health hazard . Retrieved from

Turner, B. (2010, May 26). Health effects of plastic water bottles. Retrieved from

What is PET? (2009). Retrieved from




Balloon Rocket Lab!!

Work is the application of force over distance. For example, if I lift a soccer ball off of the field, and carry it over to my locker, I am doing work. The formula for work is Work = force x distance. Work is measured in Joules (J).

Power is measured in Watts (W). It’s formula is Power = Work/Time. “Power is the rate at which energy is transferred, used, or transformed.”- Wikipedia. Continuing the example with the soccer ball, if it took me 2 minutes to get the soccer ball to the locker, to measure the power, it would be work/2 minutes (time). Energy is the ability to do work. The types of energy that would apply to this Balloon Rocket lab is, kinetic energy, thermal energy, potential energy, elastic potential energy, and sound energy. But, only kinetic energy and elastic potential energy helps the movement of the balloon. Energy is also measured in Joules (J).

The gravitational force and the normal force were equal in this lab experiment. The thrust force is greater than the friction because it is what makes the balloon move forward. If the thrust force is larger, it travels. If the friction was larger, the balloon wouldn’t move because it would be held behind. In the second image, the trust decreases since the balloon eventually stops.

<——- ——->
This would be the reaction force pair. This is because the balloon is releasing air on the left side of the string, but it is moving horizontally to the right side. This is why the reaction force pair consists of two arrows going opposite ways.  It symbolizes the  movement of the balloon across the string, releasing air to the right side.

The air that is leaving the balloon, has air that is pushing against it too, this makes the balloon move forward. The air is pushing on the balloon to create movement.

This is my video:

The method:
1.) Tie a string onto two areas.

2.) Put the string into the straw.

3.) Blow up the balloon.

4.) Tie the balloon to the straw.

5.) Let go and record the balloon.

6.) Repeat this step 5 times.

The controlled variables are the amount air you pushed into the balloon, and the point at the string where you started the balloon rocket. Also, the straw, length of string and tape are other controlled variables. In this experiment, we were not looking for differences or changes, so there were no independent variables.  The dependent variable is the work of the balloon.

The mean distance for this data is 5.50m and the mean time for this 1.5s.

The weight was 1.5 grams. The mean work is force x distance. The force is 1.5g x 10N which is 15N. So, 15N x 5.50M = 82.5 J. The work was 82.5 J.

The power is calculated work/time. 82.5 J/1.5s. This equals 55 W.

The uncertainty for the distance is ± 0.01. The uncertainty for the weight of the balloon is ± 0.01. Finally, the uncertainty for the time of the travel is ± 0.01.

We measured the time of the balloon to travel with a stopwatch, and the distance the balloon travelled with a meter stick.

This data is fairly accurate and reliable. I noticed that the data I received were closely related to each other, the range was not far. One down point was the size of the balloon, was different each time, even though I used to same amount of blows to fill it up. This also makes it somewhat unreliable.  The data is valid though, since I received the data that worked, and it gave me a valid work and power.

Elastic potential energy is the potential energy stored in the change of an elastic object. This elastic potential energy transformed into elastic energy, kinetic energy, sound energy, thermal energy.

Lost energy is found in the beginning, since the air from the balloon is distributed in different paths. Also, the amount of air released is uneven. Energy is also lost by the friction caused between the string and the straw.  Efficiency is the ability to accomplish a job with a minimum expenditure of time and effort. (, 2011). If we were to do this experiment once again, I would change some of the measuring tools we used, such as straw. We could have used smaller, thinner, and shorter straw to reduce the energy lost due to friction. Also, the meter stick, which we used to measure the distance the balloon travelled. A tape measure would have been more efficient and accurate.

To extend your conclusion to Level 5-6 for Knowledge and Understanding
The weight of the balloon we used was 1.5grams. The force (thrust) is 15 Newtons. This is the thrust force of our ballon. Calculating this, the assumption of the balloons force being 0.5N, is wrong. There is a great difference between 15N, the accurate thrust force, and the assumed thrust force of 0.5N. The assumed thrust force is way to little, and light.
Elastic potential energy. (n.d.). Retrieved from
Taylor, S. (n.d.). “How is energy used to produce change?”. In Energy, work & 
       power. Retrieved December 14, 2011, from

What is power?
 (2011). Retrieved from
Work [Image]. (n.d.). Retrieved from
Criterion B:
Criterion C:
Criterion F:

Can we use a spring to measure force accurately?

Can we use a spring to measure force accurately?

To answer this question, I would say yes, but also no. This is because using a meter stick can be accurate but also inaccurate at the same time. But, since we did these trials three times, and found the mean, this could be accurate. It is also time consuming. But, this was a fun hands-on lab we did in physics class recently.


In my group, was Jemima and Marie. We measured different weight on a spring for this assignment. The materials were provided in class, which were, a huge stand where the spring would hang, spring, weights, and meter stick. The way this worked was: once we attached the weights at the bottom of the spring, and we would measure the amount of centimeters dropped by the meter stick. It is a simple and efficient method to use. Since, it is not the most accurate, we took trials of three for each different weight to be accurate.  Since we did these three trials, our validity increases.   The independent variable in this assignment was the weight of the object (kg). The dependent variable is the length of the spring (cm). The controlled variables were the different amount and weights we hung on the end of the spring.      

With the table, is the observation which states: The spring moves down about 3-4 centimeters every time an extra weight is added. This is a pattern. So by this observation, we can see the resemblance in the trend line that was placed on the graph.

After collecting all the data and doing the previous steps of this lab, Mr. T gave us the mystery weight. For, this, we observed the centimeters it dropped and compared it to the previous observations. The mystery weight dropped in between 23.0 centimeters and 24.0 centimeters. So, we concluded that it would be 23.5 centimeters. As you can see in the graph, it is between the 2.0 and 2.5 Newtons. And, the middle of those numbers is 2.25 Newtons. We were actually really close to the actual weight, which was 2.25 Newtons. This makes the percent error 0.02% since the difference between 2.2.5N and 2.27N.


I think I deserve I MYP 4 because I feel like I did not reach up till the MYP5-6 band. I completed what was required in the MYP3-4 band, but I think I worked better than a MYP3. I think I should have worked better and tried harder to work up till the MYP5-6 band.