1. Gravitational Interaction
Brooke Young
Brandon Mock
Javier Aranguren
Ameila Spilde

2. Major Concepts
All forces of objects are due to interaction. There are four types of fundamental processes responsible for all observe processes are: Strong, electromagnetic, weak and gravitational. Gravitational Interaction is weak, fundamental interaction between two physical objects due to their mass and energy, especially an interaction occurring between elementary particles. All forces of objects are due to interaction. There are four types of fundamental processes responsible for all observe processes are: Strong, electromagnetic, weak and gravitational. Gravitational Interaction is weak, fundamental interaction between two physical objects due to their mass and energy, especially an interaction occurring between elementary particles.
The Gravitational Interaction, some 10^40 times weaker than the electromagnetic interaction, it is the weakest of all. The force that it generates acts between all bodies that have mass and the force is always attractive. The interaction can be visualized in term of a classical field of force in which the strength of force falls off with the square of the distance between the interacting body. The hypothetical gravitational quantum, the graviton, is also useful concept in some contexts. On the atomic scale, the gravitational force is negligibly weak, but on the cosmological scale, where masses are enormous, it is immensely important in holding the components of the universe together. Because Gravitational Interactions are long-ranged, there is well-defined macroscopic theory in general relativity. At present, there is no satisfactory quantum theory of gravitational interaction.

3. Historical Perspective
Every one knows that objects fall because of gravity, even before Newton. Newton did not discover gravity, but discovered that gravity is universal. It is the same force that pulls an apple off a tree, holds the moon in orbit, and that both Earth and the moon are similarly held in orbit around the sun. He also discovered that all objects in the universe attract each other.

4. Application of Concepts
Weight differs according to the gravitational pull of the nearest large body. On Earth, a person weighs a certain amount, but on the Moon, this weight is much less, because the Moon possesses less mass than Earth. Therefore, in accordance with Newton's formula for universal gravitation, it exerts less gravitational pull. By contrast, if one were on Jupiter, it would be almost impossible even to stand up, because the pull of gravity on that planet (with its greater mass) would be vastly greater than on Earth.

5. Think and Exlain
-The value of G (that is, Newton’s universal gravitational constant) would remain exactly the same, as it is not dependent on the size, shape, or other properties of a third rate little planet in a minor solar system in an obscure corner of an unremarkable galaxy.
The value of g, which would be the gravitational acceleration on the Earth’s surface (and which varies between locations, due to changes in altitude and local variations in the thickness and composition of the Earth’s crust) would double. That is because, notwithstanding the aforementioned minor variations, the value of gg is given by g=GM/R2, where M is the mass of the Earth and R, its mean radius. If R is kept constant while M doubles, g doubles as well.
2- The acceleration due to gravity or g is inversely proportional to Radius or r square.
If mass is kept constant and G being universal gravity constant, radius is halved, then as radius decreases acceleration due to gravity increases, the new acceleration due to gravity becomes 4 times g or 4g.

6. 3- He was measuring the attraction between two masses
3- He was measuring the attraction between two masses. He discovered the greater the distance from Earth’s center, the less an object will weigh.
4- Objects with mass produce a gravitational force on each other. Time and light can also be affected.
5- By Newton's 3rd Law, the weight of the Earth in the gravitational field of the Earth is equal but opposite to the weight of the apple in the gravitational field of the Earth. So the answer is 1N.
6- If the planet is shrinking, then the same amount of mass is being crunched into a smaller space. Because the force of gravity depends on mass, not volume, if you stood on a shrinking planet, your weight would be the same. However, since the distance from you to the center is less, your weight would be slightly more.

7. 7-Yes, is falling with the same acceleration and velocity as you are
7-Yes, is falling with the same acceleration and velocity as you are. Because you and the groceries are falling at the same rate, it never reaches your feet.
8-The moon is always new during (and just before) a solar eclipse and always full just before (and during) a total lunar eclipse.
9-No, yes
10- Upon this collapsed, the force of gravity at the surface increases dramatically. The gravitational force at the surface of a collapsing star increases because the star is getting smaller.

8. Review Questions
1-G stands for Newton's universal gravitational constant, whereas g stands for the acceleration due to gravity at a certain point.
G is a constant throughout space and time and it is a scalar quantity.
g is acceleration due to gravity which is a variable quantity and a vector qualtity.
2- Depends on the mass of the planet and the radius from the center of the planet.
3- In 1798 Cavendish and co-workers obtained a value accurate to about 1%. When asked why he was measuring G, Cavendish replied that he was "weighing the Earth"; once G is known the mass of the Earth can be obtained from the 9.8m/s2 gravitational acceleration on the Earth surface and the Sun's mass can be obtained from the size and period of the Earth orbit around the sun.

9. 4- They are both correct, the field that the earth emits interacts with the object. Alos the two masses exchange gravitrons between each other.
5-Just like the gravitational force, the strength of the gravitational field around the Earth decreases as the square of the distance from the center of the Earth. Twice as far means one-fourth of the field strength.
6-At the surface of the Earth, M equals the mass of the Earth, and r equals the Earth's radius.
If you are above the surface of the Earth, then r is greater than the Earth's radius, so the gravitational force (and your weight) would be less.Below the surface of the Earth, M equals the mass of the part of the Earth that is pulling you downward, which is the part of the Earth whose radius is less than your current radius. Therefore, below the surface, M would be less and so your weight would be less.

10. 7- mass at this point will be zero, what means gravitational force would also be zero.
8-At the surface.
9-When the elevator is moving, we will weigh our normal weight. Since we are already moving at the same speed as the elevator, nothing is affecting us to change our weight. However, when the elevator starts to go or stops, our body resists it.When the elevator stops, our body wants to keep going, but the floor will not let us keep moving. So for a short time, we are pushed into the floor more and our weight goes up.

11. 10-In apparent weightlessness, both the person and his sorrundings are falling at the same rate, in treu weightlessness a person is far removed from any masses.
11-It is the difference in the distance of the water to the moon at differen times and places. Nearer implies grater attraction so the water bulges toward the moon at different times.
12-No, tides are a result of a the change in G across a body.

12. 13-Sun-Earth
14-Moon because ut is closer
15- Gravitational fields of the sun and the moon are aligned.
16-At spring tides the sun and the moon are aligned what makes a large tide. At neap tides they are not aligned so it produces a smaller tide.

13. 17-Because water is heavier.
18- Gravity and mass.
19-a stellar "black dwarf" is the end result of a white dwarf star that has radiated away its remaining energy, the accepted age of the universe is insufficient to give rise to a "black dwarf" however, a stellar black hole is the end result of a massive star that explodes as a supernova with the remnants exceeding about 3 solar masses, such a remnant cannot produce energy to counteract gravitational contraction and it is compressed into a "stellar mass" black hole.
20- It would exert no more gravitational force on Earth or the other planets in the solar system than it does now because it would contain no more matter than it does now and it would be no closer to the planets than it is now.

14. Framing
Everybody knows there is a thing called "gravity". Many people believe Newton was the one that discovered gravity, but he actually is not. Newton found that gravity was universal but not ctuslly gravity itself. Newton discovered that all objects in the universe are attracted to each other. Also the same force that makes a pencil drop is the same force that hold the moon in orbit.

15. Question
How does one coin change weights just by moving your hands?

16. General Statement
This experiement shows weight and weightless in the gravitational interactions chapter. It will involve a coin and a hand showing the difference from free falling and being pushed.

17. Materials
A hand
A coin

18. Procedure
To begin this experiment, place a coin in a persons hand and show the coin does not move because the weight is the gravitational forcebetween the coin and the earth. Move you hand down slowly and the coin stays with your hand, but if you drop your hand quickly tht coin does not stay with your hand.

19. Safety
Keep the coin from flying across the room.

20. Diagram O <--- coin | | <--- gravity going down
____| <----- hand

21. Analysis
After conducting this experiment, when the hand is not moving the coin stays because of gravity. When risen up at a quick pace the coin actually has a greater mass than at a stand still. This is because the gravitational pull on the coin is down, so raising your hand up puts a biggger force on the coin aganst your hand. When moving your hand down faster than the coins gravity is the coin seems weightless because it is in mid air, floating, free falling. Even though it does have a weight, there is nothing measuring it so it appears weightless.

22. Conclusion
After performing the experiment, we found it showed perfectly the pull that gravity has. A con is light so feeling the difference in weight is very difficult when raising you hand up. But thinking of an elevator, when you are inside and the elevator shoots up, you feel a weight on your shoulders, heavier. When it shoots down you feel super light. This is the same concept with the coin in a smaller version.

23. Evaluation
The coin itself does not actually change weights even though it would appear to. The force moving the coin up makes it seem heavier because gravity is pullng the coin down. When the coin free falls it appears to have no weight because there is nothing touching your hand anymore. At a standstill you can feel the actual weight of the coin which is ho it always is reguardless of the environment.