Energy (Mechanical)

Hello people,,,

Today I am going to talk about Kinetic Energy and Potential Energy.

First, what is energy? Energy is the ability to cause change.

So, what is kinetic energy and potential energy? You will be surprised if you learn what it is, because it is so near to you.

To make it clear, I will tell you the definition first. Kinetic energy is the energy an object has due to its motion. If object isn’t moving, there is no kinetic energy, and Potential energy is the energy stored in an object because of its position.

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It is hard to understand with these definitions, right? Okay. I will give you the examples. Let’s say there is a person on the bungee jumping. If a person is at the highest place, which is the place you jump, it means a person has most potential energy. When a person falls, the person will gradually get a kinetic energy. When a person reaches the bottom, the ground, it means a person has the most kinetic energy. When a person weights more, a person has more potential energy. If I say it easier, potential energy depends on its mass and height
bungee jumping

Different with potential energy, kinetic energy depends on mass and speed. When the person weighs more, and when speed is faster, person has more kinetic energy than lighter person.

 

Energy can be transferred and stored. Energy gets transferred when objects collide. I will make an example with bowling. When the bowling ball gains energy by a person who throws the ball, and when it rolls, it has kinetic energy. When the ball collides with the bowling pins, pins are gaining the energy. Since the pins don’t have wheels, it knocks out. Additionally, energy can never be destroy or created. It just looks like they do, but they are only changing the forms of the energy like potential and kinetic.

I got definitions by the textbook physics!

I hope you understood!

Matter Changing

 Im back! It's been long time to post.. Sorry! Today I am going to talk about the states of matter. It is not hard, and it will not confuse you. So follow me!!
What is matter? Matter is anything that takes up space and has mass.
There are three main states of matter. It is solid, liquid, and gas. There are couple more like plasma and colloid. Plasma is energy, that only occurs in super high temperature. Most of the structures in the universe is made of plasma, but there are really few in earth. Lightning is plasma, and stars are all plasma. Colloid is things like jelly, paint and rubber. You don't need to think about these, but three states solid, liquid and gas.

neon

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Solid
Solid is matter with definite shape and volume. The common example of solid is ice, frozen water. If you put the ice in a beaker, you won't see ice changing it's shape. An ice will retain their shape even you put in container.
If you put an ice at the room, it will melt. Melting is what we call when solid changes to liquid, like an ice changing in to water. Do you know why melting happens? It is because of temperature of the room. Water tend to stay at state of liquid when the temperature is between boiling point (100°C) and freezing point(0°C), also called melting point(0°C). 
Heat of fusion is also heat energy that helps to break the state of solid.
Additionaly, heat of vaporation is energy that adds to liquid to change to gas.

Liquid
Liquid is also the state you would see easily around you. It has definite volume, but not definite shape. If you pour the water in different shape of containers, the shape of water changes as the shape of container. Water is only formed when the water (H2O) is between the temperature of 0 and 100 degrees of Celsius. Liquid vibrates just like the other states, but not more than gas does.

Gas
Gas is when the state gained the most energy. The gas tend to move farther and farther. In the state of gas, water molecules move around randomly, free! But one thing you really have to remember is that when the state of water changes, that doesn't mean the chemical properties changes, but it is only physical change. Chemicals retain as water molecule (H2O) doesn't matter what state the water is. 

Water

Sublimation is when solid matter changes to gas without the step of liquid. OR it can work opposite. The example is dry ice. Dry ice can change to gas right away. 
Condensation is when gas changes to liquid. For example, when there is a cup of water, and if you put in your room, the surface of the water bottle will have drops of water sticking on the side. The water on the side of the cup is happened because of the gas around the cup.
Deposition is when gas changes to solid opposing sublimation. When the when the vapor on the air changes to frost, that is deposition. You can see this in the morning at cold area.

condensation

It is not true if you think all the matter has the same boiling point and melting point. Water is just one good example. Dry ice is the state of solid of carbon dioxide. In the case of dry ice, this changes to gas(sublimation) in the temperature of 25°C, not 0°C. So you need to remember that not all the matter has the same boiling point and melting points.

DONE!!!!!!!!!!!!!!!!SEE YOU NEXT WEEK!