Wave properties

H.Pulse wave

Non-repeating wave, single disturbance.


I. Periodic wave

Regularly repeating disturbances.


J. Transverse wave

Spring is pulled sideways, and the wave across the spring to the direction that the wave will travel.


K. Longitudinal wave

Spring are compressed and let go, Disturbance is in the same direction as the direction of travel.


L. Destructive interference

The energies combine to work against each other as the periodic wave, the crest and trough tend to cancel out when two waves meet.

The video is the same as periodic wave.

M. Constructive interference

When two same size crest or trough meet from different direction, the energy of two wave combine to form a bigger wave when they meet.


N.Standing wave 

have the same amplitude and wavelength, the resultant interference pattern remains nearly stationary. A node/nodal point remains at rest throughout the interference of the pulses.


Thermos Challenge

Prototype testing procedure:

1. Heat up 150ml of water in a beaker on a hot plate set to high and heat it up to around 100 °c.
2. Take the initial temperature of the hot water as soon as it poured into the prototype thermos. Record the temperature and quickly place the cap on the thermos.
3. Leave the water for 20 minutes and observe any changes in the heat on the outside of the thermos.
4. Remove the cap and record the temperature of the water. Calculate the final and initial temperature difference.
5. Note any flaws and possible improvements that could be made to the design.
6. Make improvements based on the notes and repeat the procedure with the next prototype.
The idea behind this prototype is to reduce heat loss through heat transfer, so we use a lot of materials that have less thermal conductively, so the conduction of heat through the contact between the hot water and the material becomes weaker and slower.

Prototype #1









Materials list and cost










1.Pretty cheap. Cheapest one in all three prototype.


1.The appearance is simple, not attractive.

2.The lid (ballon) is not easy to take off, it takes time and will loss the heat by Conduction.


– Improve external insulation to reduce heat loss.

– Try another material to make the lid.

– Add decoration to make themes look better.

Because sand has strong thermal conductivity and is easy to absorb thermal energy, we add sand between the cups, so that the sand absorbs the heat of water, and plays a role of heat insulation through the sand. On the other hand, due to the heat loss caused by convection inside the water, a large amount of heat of water molecules with higher molecular kinetic energy will move to the surface. If there is no cover, it will cause a large amount of heat loss, so we use a cut balloon As a cover.









Materials list and cost











2.General insulation effect.


1.The appearance is simple, not attractive.


– Try to add aluminum foil inside the foam cup, to absorb heat.
– Add decoration to make themes look better.
We made the second idea based on the first one to reduce heat transfer and enhance the heat reflection in the inner layer. Since aluminum foil has very strong thermal conductively, if used in the inner layer, it can strengthen thermal reflection and achieve the effect of ” reheating ”to keep heat. With a lid made of the foam cup, it can reduce the heat loss caused by convection inside the water.









Materials list and cost











1.Better insulation effect.

2.Beautiful appearance.


The coffee cup lid have a hole on the top, which will loss heat through the hole.


-Find something to cover the hole on the lid to reduce or slow down the heat dissipation.

-Use aluminum to cover the lid, to achieve better insulation effect.

The third major is a combination and improvement of ideas. We have used the aluminum foil in the second experiment to achieve the internal thermal insulation effect of “reheating the water.” It can better achieve the effect of external insulation.


Final Product

Materials list and cost
















Our final product evolved from the third prototype, we proposed to add improvement of aluminum foil to the lid, and our final product is to test our hypothesis and improve. Since aluminum foil has very strong thermal conductively, if used in the inner layer, it can strengthen thermal reflection and achieve the effect of “reheating” to keep heat. The lid is made of aluminum foil, on the one hand, because of material price, on the other hand, because in the interior of the water can produce heat loss by convection, high quantity of heat of water molecules have higher molecular kinetic energy will move to the surface, if there is no lid can cause a lot of heat loss, and we want to use radiation of aluminum foil to reduce heat loss.
Overall, water in the prototype lose heat main is by conduction, so we are doing the project’s main idea is to use less thermal conductivity of materials to reduce heat conduction, so each of our design in outer do have “shell”, and through the results of the first we knew, the “shell” is not enough to reduce conduction, we need to strengthen inside, so we adopt with radiation heat material for “heating water again”.And at the top of the design is similar to the cup body, which is also using thermal conductivity less to reduce heat loss. But the second main consideration is the use of radiation, which reflects heat, to conserve it.


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Man with Hat

Eric, an ordinary worker, one day had a superpower, which was to become transparent. He had this power after he got a black hat, he was pretty surprised with the power of that hat. However, when he put on the hat, his body became transparent, but his clothes were still on his body. When he walked on the road with a black hat, people who saw him was very frightened, there were some people fainted. Through experiments, Eric found that if he wanted anybody not to saw him, he must not wear anything but a black hat.

Eric had an idea: Nobody could see my face if I put on the black hat. I could use my superpower to steal, so I didn’t have to work hard anymore. And the police would not have any idea to catch me.  Eric hid in the department store and wait for the chance. At midnight, there is nobody in the store, expect some security. Eric used his superpower and stole some luxury. He was pretty excited and hold these bag back home. This was the first time commit.

Eric became more arrogant after one win. He started to commit crimes, the value of the stolen goods is also higher than once. Eric fell in love with this feeling, he was more and more fearless. He is becoming more and more greedy, and the value of stealing is getting bigger and bigger. However, his arrogance attracted the attention of the FBI Special Capabilities Group. They found out that Eric’s ability came from the hat. When Eric was once again stealing, the FBI worked together to stop Eric and successfully knocked the hat over to the ground. Eric didn’t have his source of power and revealed his true body. Eric was arrested and sentenced to reimbursement of stolen goods. He was sentenced to 20 years in prison for the sheer number of thefts. The magical hat was also kept by the FBI as evidence.


  1. How is the American Dream characteristic of American ideals and philosophy? What are the differences between the materialistic and the idealistic values associated with the American Dream?

Idealistic values associated with the American Dream are the belief that reality is in our minds. This means that beliefs, ideals, principles, and values are far more important than objects such as money.

Materialistic values associated with the American Dream are the belief that all thought and actions are solely caused by objects. The only thing that matters in the world is objects. An example would be money because many people care more about the materialistic things of this world than beliefs, principles, or values.

The difference between the two is that materialistic values are only there for a short amount of time but beliefs and principles, like idealistic values, will always be there no matter what happens because materialism is limited in a way that you can’t be happy living your life based on having the most money. Money doesn’t buy happiness. But idealistic values will always keep you happy because knowing that your family is safe and sound and to reach a goal is better than having only money.

2. What was happening economically and socially in the United States in 1949? Was it fairly easy or difficult to get a job? What was America’s standing in the world?

With the world changing very quickly due to the advances in technology during World War II (1940-1945) what had been a good job or product may have seen it’s last days.

Also with all of the veterans coming back from War and being discharged from the service good jobs were almost impossible for them to find. It may have taken 5 or 6 years or so before the veterans could find a permanent, well-paying job.

3. What is your definition of the salesman? How is a salesman different from someone in another occupation? What attitudes do you think a salesman should have to be successful? What attitudes would hinder him?

It’s basically a guy who sells stuff. He has to move everything to sell something and he doesn’t have a fixed salary. He has to be patient and real gentleman, a gifted speaker. Impatient, short temper, mean, smells bad.

4. What effect do the expectations of parents have on the behavior of their children? In what ways might parental expectations be beneficial? In what ways might they be detrimental?

Parents have a great deal of influence on their children, especially when the children are young.
Some of that influence is beneficial, and other times it is not. Children are very influenceable by the parent’s expectations. Children can be stressed. The expectations can also be too low and not give the extra push the kid will need to become successful. Expectations can be too high for the kid. Some kids will go along with what their parents want for them. Others have a mind of their own. If parents push too hard, they will lose the trust and confidence of their children, and they will go their own way.

What I think the American Dream is

What is the American Dream?

Before I started writing, I asked myself:What exactly is The American dream, and does it even exist anymore, and if so, does The American Dream have the same meaning today as it had in the past? Is The American Dream only for Americans, or do people from around the world still move to the U.S., hoping to achieve their dreams?

“American Dream” was invented during the Great Depression. The years that followed after the Great Depression, The American Dream came true for many of the young people, however,the definition of The American Dream has changed over the years. The American Dream is still alive; it just depends on how you define it. For me, The American Dream is about success in terms of what you wish for. Compared to many other countries in the world, America is a place where you have the opportunity to determine your own success. Everyone has different jobs which can control how successful they are or want to be. I believe that most dreams revolve around one’s happiness and well-being, is achievable for all.  In fact, it has a different meaning for each of us, but I’m sure we can all agree that the American Dream includes hope for a richer life with freedom and opportunity.