Limited Notes:

All matter has energy, matter made up of molecules or atoms.

An atom is the smallest particle of an element with all the properties of that element. Some examples of elements, and their chemical symbols, are Copper, Cu; Iron, Fe; Gold, Au; Silver, Ag; many gases are diatomic, or they travel in pairs: Hydrogen, H₂; Oxygen, O₂, some gases are monatomic and that is they travel as single atoms, like all of your inert gases, starting with Helium, He; Neon, Ne; Argon, Ar, and so on.

A molecule is the smallest particle of an element or compound that has all the properties of that element or compound. A molecule consists of two or more atoms, these atoms can be identical or different, if they are different, then they are referred to as a compound.

Water molecules are made up of two hydrogen atoms and one oxygen atom, on the other hand pure oxygen is made up of molecules that consist of two oxygen atoms, so oxygen is an element and a molecule. Hydrogen gas also travels in pairs, and is also referred to as a diatomic gas. The reason why oxygen and hydrogen are diatomic gases, is because they tend to share outer electrons with other oxygen or hydrogen atoms. This gives them a bit more stability.

When you place an object on the table, say a book, that book now has potential energy. So Potential Energy can be considered as energy of position. It now has potential of doing some work. When you push that book off the table, that book now has Kinetic energy, or energy of motion. The same thing would be true, if you had an old type of wrist watch, where you had to wind it up. When you wind it up, the watch now has stored potential energy, when you give the watch a shake and start the second hand moving, it now has Kinetic energy or energy of motion.

The bolt on the pendulum at rest, at point " B " has potential energy, you could cut the string and change that into kinetic energy. When you lift the bolt of the pendulum to a certain ( height ) length, it now has potential energy, and as soon as you let it go it now has kinetic energy or energy of motion. When the bolt reaches the other end, for a split second it stops, and has potential energy, when it starts down again it has changed to kinetic energy.

In liquids, molecules are allowed to move freely or slide over one another, an English scientist named Robert Brown in 1827 had observed the movement of pollen grains with a microscope, moving in a zigzag pattern, and in his honor this movement was named the Brownian movement.

Since, matter has energy the molecules or atoms that make up matter are in constant motion, this is not so evident. In solids, molecules are fixed in position, but they vibrate. The question could be asked is; how cold is cold ? Scientist has been able to get close to the absolute zero where all atoms stop moving, this temperature happens to be -273 ° C or Absolute zero, and Lord Kelvin has suggested keeping the Celsius scale, but adding the 273° to the Celsius sale, the result would be, all calculation would be positive. And in Lord's Kelvin honor, this Absolute temperature scale was named Kelvin scale. So that you might see a temperature reading ° A or ° K which means the same thing. Since you can equate moving molecules with energy, the faster the movement of a molecule the more energy it has, hence, the higher the temperature the higher the energy the molecule would have. Now, in solid you cannot see the molecules move or vibrate, but you can take the temperature of solid and assume that the higher the temperature the more energy the object has. Check out the experiment on " Molecules " for further explanation.

Kinetic-molecular theory; basically states that molecules of matter are in continuous motion and an increase in temperature increases the molecular motion.

Judges 9:53 And a certain woman cast a piece of a millstone upon Abimelech's head, and all to brake his skull. 56 Thus God rendered the wickedness of Abimelech, which he did unto his father, in slaying his seventy brethren:

Towers played an important role in towns of the Old Testament. In case of an attack, people would run to them for a safe refuge, they were constructed from stone, were quite high, one door entrance, made with heavy wood and reinforced with lots of iron or brass. There were provisions stored in the tower, and lots of defensive weapons, so any body approaching the entrance, would be rained upon with anything that they could carry up to the tower. Millstones were carved from large rocks, and in this case, the rock must have fractured while being fashioned into the round stone, so what better use to put it to, is to make it part of the defense. That piece of millstone had to be carried up to that tower, and when that certain women dropped it, it turned from Potential energy to Kinetic energy, or energy of motion, such that it had the capability or potential of cracking the head of Abimelech.

The towers were quite high, and at night a small fire on top of the tower, would served as beacons to travelers, and in a level terrain, they were seen from a great distance.

PROBLEM:

To observe a change from Potential Energy to Kinetic Energy.

MATERIALS:

PVC stand, string, large nut, clock or watch with second hand.

PROCEDURE AND OBSERVATION:

1. Set up the following apparatus, as shown in the above diagram.

2. A complete swing starts at point A and ends at point A.

3. It would be helpful to have an assistant, to watch the clock, while the other person counts the complete number of swings, or have the clock or watch in back of the Pendulum, so that you can see both.

Chart A

TRIAL	NUT	LENGTH OF STRING	AMOUNT OF SWING	TIME	# OF COMPLETE SWINGS
#1	________g	1 FOOT	6 inches	1 MIN	______
#2	________g	1 FOOT	6 inches	1 MIN	______
#3	________g	1 FOOT	6 inches	1 MIN	______
					AVERAGE _____

Chart B

TRIAL	NUT	LENGTH OF STRING	AMOUNT OF SWING	TIME	# OF COMPLETE SWINGS
#1	________g	1 FOOT	3 inches	1 MIN	______
#2	________g	1 FOOT	3 inches	1 MIN	______
#3	________g	1 FOOT	3 inches	1 MIN	______
					AVERAGE _____

Chart C

TRIAL	NUT	LENGTH OF STRING	AMOUNT OF SWING	TIME	# OF COMPLETE SWINGS
#1	________g	6 inches	3 inches	1 MIN	______
#2	________g	6 inches	3 inches	1 MIN	______
#3	________g	6 inches	3 inches	1 MIN	______
					AVERAGE _____

Chart D

TRIAL	NUT	LENGTH OF STRING	AMOUNT OF SWING	TIME	# OF COMPLETE SWINGS
#1	________g	6 inches	2 inches	1 MIN	______
#2	________g	6 inches	2 inches	1 MIN	______
#3	________g	6 inches	2 inches	1 MIN	______
					AVERAGE _____

QUESTIONS:

1. Define Energy -

2. Define Kinetic energy -

3. Define Potential energy -

4. In chart A and B is there any connection between the number of complete swings, and the length of the swing ? Explain your answer.

5. What is the connection between the length of the string and the number of complete swings ? Explain your answer.

6. What kind of energy does the pendulum nut have at point "A" __________ , point "B" ________ , and point "C" _________. ?

7. Explain how the kinetic - molecular theory accounts for the increase in volume of a gas, that is heated .

8. Define Kinetic-molecular theory -

9. Give an example where each of the following forms of energy is produced. (a) mechanical (b) sound (c)electrical (d) chemical (e) light

10. A burning piece of coal would involve what forms of energy ? Explain your answer.

11. In Africa, there is nothing that goes to waste, all carcasses are picked clean, and you would think, that there is nothing else to be eaten. However, there is a bearded vulture called a lammergeier, that likes to eat the marrow from dead animal bones, his beak is not strong enough to crack bones, so he takes the heavy bones up into the air and from a considerable height, he drops the bones on the rocks. These bones fracture and then he is able to eat his marrow and pieces of bones. At what point are the bones considered to have Potential energy and at what point are they considered to have Kinetic energy ?

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