Center of Gravity By Heston Forson, Aaron Cathcart, Nathan Ireland and Bailey Sprague.

State and Explain Major Concepts Center of gravity: The point at the center of an object's weight distibution, where the force of gravitycan be considered to act. Center of mass: The point at the center of an object's mass distribution, where all its mass can be considered to be concentrated. For everyday conditions, it is the same as the center of gravity. Neutral equilibrium: The state of an object balanced so that any small rotation neither raises nor lowers its center of gravity. Stable equilibrium: The state of an object balanced so that any small rotation raises its center of gravity. Unstable equilirium: The state of an object balanced so that any small rotation lowers its center of gravity.

Historical Perspective Center of gravity was first studied by Archimedes. and other Physicists have opened it more. The Physicist Leibniz, focused more on triangles for the center of gravity, while the Physicist Carl Clausewitz delved more into war fighting uses of the center of gravity. Clausewitz had many studies showing that a blow would be more effective if aimed toward a center of gravity of an object. And also studied by Raffaele Pisano during the renaissance.

Application Concepts You can use the concept of center of gravity to find the proper area of balance in an object, you can also use center of gravity to predict the path of an object after it dispurces into smaller objects, such as a firework exploding. The shrapnel would move along the same path after the explosion because they have the same center of gravity.

Think and Explain Questions 1) The center of gravity of the wheel should be located in the center of the wheel. 2) A washing machine vibrates violently when clothes are unevenly distributed because the center of gravity is constantly changing 3) We speak of the center of mass instead of the center of gravity because center of mass is the point at which the distribution of mass is equal in all directions, and does not depend on gravitational field where as the center of gravity is the point at which the distribution of weight is equal in all directions, and does depend on gravitational field. 4) The glass with the liquid in it is unstable and will topple because since it is filled with a liquid the liquid will shift all to the side of the glass that is the lowest so it will then become heavier on that side and topple. 5) In figure E, the bicycle with a person hanging down on each side is in stable equilibrium because the center of gravity is below the point of support, the man straddling the rope has a neutral equilibrium because his center of gravity is neither raised or lowered with displacement. the man with the monkey on his head has an unstable equilibrium because any displacement would lower the center of gravity. 6) To stack the bricks so that the top brick has maximum horizontal overhang above the bottom brick you must put the end of the top brick behind the center of gravity of the brick under it for each brick. 7) Tall floating icebergs do not tip over because they have a stable equilibrium because the center of gravity is below the point of support a.k.a. the surface of the water. 8) Work is required to push a tennis ball beneath the surface of a glass of water because the same volume of water is more dense then the tennis ball so the center of gravity of the whole system would be lowered. 9) A pregnant woman or man with a large paunch lean backwards when walking because they naturally have a more forward based center of gravity so they lean back to counter balance the weight. 10) Reasons why females can lift the chair up is because there center of gravity tends to be slightly lower then males because they tend to be proportionally larger at the pelvis area and smaller at the shoulders.

Review Questions 1. The center of gravity of a baseball bat is not at its center because it is irrelgularly shaped so the center of gravity needs to be towards the end of the bat that weighs more. 2. The center of gravity. 3. The center of gravity follows the same path as before it explodes. 4. For almost all objects on and near Earth the terms are interchangeable, but in space where the force of gravity is basicaly zero, an object will have a center of mass but no center of gravity. 5. It has planets around it. 6. By using a plumb bob. 7. A boomerang. 8. It doesn’t topple because its center of gravity lies above its base. 9. Until its center of gravity extends beyond its support base. 10. The movements you make with your hand to keep it balanced are similar to how the computers keep the rocket upright. 11. An object balanced so that any displacement lowers its center of gravity is in unstable equilibrium, an object that is balanced so that any displacement raises its center of gravity is in stable equilibrium, an object that is neither raised or lowered with displacement is in neutral equilibrium. 12. It is more. 13. Because when you hang below a cable your center of gravity will be below the cable making you stable and when you do a handstand on a floor, your center of gravity will be above the floor making you unstable. 14. They are weighted so the center of gravity lies below the point of support while most of the rest is above it. 15. Its center of gravity is below ground level. 16. The center of gravity is lowered. 17. The center of gravity is raised. 18. It makes their center of gravity lower and requires less work to clear the bar. 19. It widens your support base and makes you more stable. 20. You cant because when you bend over this way your center of gravity extends over your toes and you would fall over.

Question and Hypothesis How far would we have to raise the base to have the given object topple? I hypothesize that the block will topple at a higher angle of slanting than the brick.

General Statement of How We Conducted The Demonstration We will first collect our materials, then place first object, the block on the base, then raise one side of the base so that the base is on a slant by one centimeter until the object topples, then record data, then the second object, the brick on the base, then raise one side of the base so that the base is on a slant by one centimeter until the object topples and then finally record your last set of data.

Apparatus and Materials Ruler that measures centimeters Slantable base "length 29.4 cm, width 21.7 cm, height 1.7 cm" Objects to topple "Brick and Block" Brick"", Block " length 12.5 cm, width 3cm, height 25.3 cm" Plumb line Pen and paper to collect data Scotch tape

Step By Step Instruction For Doing The Demonstration. Collect materials 2. Place first object, the block on base 3. Raise one side of the base so that the base is on a slant by one centimeter until the object topples 4. Repeat steps two and three two more times 5. Record all data 6. Place second object, the brick on base 7. Raise one side of the base so that the base is on a slant by one centimeter until the object topples 8. Repeat steps two and three more times 9. Record data

Safety Precautions Dropping objects such as bricks and blocks on toes.

Collecting And Presenting Data Object being toppled Height of Toppling Block 10.5cm Brick 14.0cm

Analysis of Results The results we received from our experiment shows that the block toppled later and which shows that the block has a larger base proportional to its height than the block.

Conclusions Supported By Evidence The results that we received from our experiment gives evidence that when an object has a larger base perportional to its size it will topple later than the object that has a smaller base perportiaonal to its size.

Evaluation of Hypothesis and Answer to Our Question My hypothesis was that the block will topple at a higher angle was correct and our answer to our question was that the block toppled at 10.5 centimeters and the brick toppled at 14.0 centimeters.