## Thursday, November 11, 2010

Today in class we talked about the five different types of energy. The five of energy are:

• Nuclear Energy
• Light Energy
• Mechanical Energy
• Electrical Energy
• Chemical Energy

We specifically talked about how these types of energy can transform into different types of energy. For example, a crank radio changes mechanical energy into electric energy. The mechanical energy is when you turn the crank and the electric energy is when the radio turns on and finds radio waves and then projects the sound out of itself.
Next in class we talked about the types of mechanical energy which were:

• Kinetic Energy
• Internal Energy
• Gravitational Potential Energy
• Elastic Potential Energy

We then reviewed our homework from Monday and in the first four questions we switched our made names for the situations and inserted the scientific names. The answers were:

a) The external force caused the block to move higher above the Earth’s surface.
Gravitational Potential Energy
b) The external force caused the cart to move faster and faster.
Kinetic Energy
c) The external force caused the slingshot to stretch.
Elastic Energy
d) The external force caused the surfaces of the touching objects to warm.
Internal Energy

During the discussion about those questions we decided that Gravitational Potential Energy meant that gravity had a chance to pull it down to the ground. We also found out that Kinetic Energy was the speeding up of an object not the moving of an object. If you have trouble with this concept just think of when Doc. Fin pushed MK across the room and that it was only Kinetic Energy when MK was being pushed because once Doc. Fin let go negative force was starting to be applied.

Then we answered the first 2 questions of the next section.

Examine the picture to the left. One of your classmates says, “When the car gets to the edge it will have ‘the ability to fall’ or ‘falling ability.’”
a) If the Earth weren’t there, would the car still have “falling ability?” Explain.
b) Should we include or exclude the Earth with the car when we analyze this problem?
For the first question we said that if the Earth wasn’t there than the car wouldn’t have falling ability because the Gravitational Potential Energy that affected the car would be gone. The next question’s answer is that we should include the Earth with the car when we analyze the problem because our results from the previous question show that the Earth is what gives the car falling ability.
Lastly before the bell rang we discovered that every mass has a gravitational pull these masses could be as big as the earth or a small as a chair.
-DB