Proudly Present WELC OME TO OUR PRESENTATION

1. ATIKA ULYA AKMAL / 16019/2010 G R O U P 5 ELMA RAFIKA/ 18049 / 2010 GRAVITATION 3 1 2 Proudly Present WELCOME TO OUR PRESENTATION

2. INTRODUCTION THEORITICAL MISSCONCEPTION ELABORATION CLOSING PENDAHULUAN

3. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: INTRODUCTION PENDAHULUAN 1.Physics is basic science that has relation with the nature fenomenas. Some field of physics such as motion, fluids, colour, heat, electricity, light and magnetism, and topics at modern physics like relativity, structure of atoms, solid substance, nuclear physics, particle of elementary, cosmology and astrophysics. 2.Physics was developed from observations and experiments. Experiments were carried out using the scientific method. 3. In understanding the concepts of physics that scientists have been developed, there is the possibility of differences in understanding of physics concepts. HOME NEXT

4. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: INTRODUCTION PENDAHULUAN 4. There are many causes of misconceptions in understanding the concepts, principles and laws of physics. 5. To understand the physics concepts developed to fit the scientists, it must be analyzed carefully, looking for more references 6. Gravity was developed by Isaac Newton's famous law of universal gravitation with. However, in the application of the concept of gravity in daily life, there are misconception HOME

5. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: THEORITICAL PENDAHULUAN • Newton's law of universal gravitation states that every point mass in the universe attracts every other point mass with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. HOME NEXT

6. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: THEORITICAL PENDAHULUAN • The value of "g" (9.82 m/s2) is the average measure of the strength of Earth's gravitational field (i.e., the acceleration produced on a mass regardless of the composition of the mass.) The value of "g" can vary locally depending on subsurface mass (e.g., plutonic bodies) and so the value (9.82 m/s2) is an average. HOME

7. Missconception About Gravitation • 1.The moon is not falling • 2. The moon is not in free fall • 3.The force that acts on apple is not the same as the force that acts on the moon. • 4. The gravitational force is the same on all falling bodies. • 5.  There are no gravitational forces in space. • 6.  The gravitational force acting on the Space Shuttle is nearly zero. • 7. The gravitational force acts on one mass at the time. • 8. Moon stays in orbit because the gravitational force on it is balanced by the centrifugal force acting on it. • 9. Weighlessness means there is not gravity. • 10.  The Earth’s spinning motion causes gravity. PENDAHULUAN HOME

8. The moon is not falling. PENDAHULUAN Moon is fall because it move with a velocity which acted centripetal acceleration (as) down to center of moon orbit (earth). We can see on the figure below. HOME NEXT

9. PENDAHULUAN Figure E-1. The gravitational force one object exerts on a second object is directed toward the first object, and is equal and opposite to the force exerted by the second object on the first HOME NEXT

10. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: Where PENDAHULUAN So that G = 6,67 x 10-11 Nm2/kg2 Mb = 5,98 x 1024 kg rb= 4,23 x 107 m so that the magnitude of moon velocity is 3,07 x 103 m/s. This value is the minimum velocity that needed by moon to move arround its orbit. HOME NEXT

11. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: PENDAHULUAN  From that equation above we can get two conclusion, those are: If the velocity is more larger than minimum velocity value, so that the moon will be flung away to outside orbit. If the velocity is more smaller than minimum velocity value, so that the moon will be attracted to the earth. HOME NEXT

12. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: 2.The moon is not in free fall. PENDAHULUAN The moon is free fall The condition an object experience the falling bodies is the its magnitude of acceleration is the same with acceleration of gravity in the earth surface. But, this motion only be act on the object that near from earth surface. Because the distance between moon and earth very near (long range order = 107) so that the magnitude of acceleration that be acted by moon very small (milliar order). HOME NEXT

13. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: PENDAHULUAN For calculate the magnitude of gravity which be acted by moon can be done with: … (5) Where, h = the distence of object from the earth surface Rb = the radius of earth HOME NEXT

14. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: PENDAHULUAN • Apogee and Perigee is called Free fall HOME NEXT

15. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: 3.The force that acts on apple is not the same as the force that acts on the moon. PENDAHULUAN • The force that acts on apple is the same as the force that acts on the moon. • The force is gravity. But, the magnitude of force that acts on the apple is not same as the magnitude of force that acts on the moon, because its magnitude depends of the distance between two objects or earth surface. If an object be on near from earth surface so it will be felt the small gravity and the other way. HOME NEXT

16. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: PENDAHULUAN The relationship between the force of gravity (Fgrav) between the earth and any other object and the distance that separates their centers (d) can be expressed by the following relationship HOME NEXT

17. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: 4.The gravitational force is the same on all falling bodies. PENDAHULUAN The gravitational force is not same on all falling bodies • The gravitational force that be felt by the falling bodies depends of its mass. This statement is true because the gravitational force is the interaction force between two or more mass HOME NEXT

18. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: PENDAHULUAN • Be in mutual accord with this equation: then … (6) Where, r = the distance of two objects HOME NEXT

19. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: PENDAHULUAN As learned in an earlier unit, free fall is a special type of motion in which the only force acting upon an object is gravity. Objects that are said to be undergoing free fall, are not encountering a significant force of air resistance; they are falling under the sole influence of gravity. Under such conditions, all objects will fall with the same rate of acceleration, regardless of their mass HOME NEXT

20. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: 5.There are no gravitational forces in space PENDAHULUAN There are gravitational force in space. But, the magnitude of gravitational force are small because the distance between an objects in the space very far. HOME NEXT

21. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: The space shuttle orbits Earth at an altitude of only a few hundred miles and Earth has a radius of a few thousand miles, so shuttle astronauts are only a little farther from Earth's center than their friends back home. Astronauts are weightless because they are in freefall not because there is no gravity in space. PENDAHULUAN HOME NEXT

22. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: PENDAHULUAN • Newton's law of gravity says there is a gravitational force between any two objects in the universe and this force weakens with distance but extends infinite distances. • Astronauts orbiting the Earth in the space shuttle are weightless, so people might think that there is no gravity in space. However this can not be true because Earth's gravity is what keeps the shuttle orbiting Earth. HOME NEXT

23. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: 6.The gravitational force acting on the Space Shuttle is nearly zero. PENDAHULUAN The gravitational force on the Space Shuttle is not nearly zero. Although, the value is small but it is still can be calculated by the equation: HOME NEXT

24. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: PENDAHULUAN • There is still a weak gravitational force in very deep space because the gravitational force gets smaller as the distance increases, but it never reaches zero. Hence in very deep space gravitational forces are very weak, but they are still there. HOME NEXT

25. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: 7.The gravitational force acts on one mass at the time. PENDAHULUAN • The gravitational force is not acts just on one mass, but the gravitational force acts between two or more mass. While an object still be on the earth surface so it is still feel the gravity from earth. For example, on the falling object. The object can be gone down causes gravity that act from earth surface. HOME NEXT

26. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: PENDAHULUAN HOME NEXT

27. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: 8.Moon stays in orbit because the gravitational force on it is balanced by the centrifugal force acting on it. PENDAHULUAN Moon stays in orbit not caused by the centrifugal force, but moon stays in orbit because an velocity that be produced sentripetal acceleration that act go in the direction to the center orbit. This explanation about that can we found on the satelite motion. If a satellite stopped moving, it would fall directly to Earth. But at the very high speed a satellite has, it would quickly fly out into space (Fig. E-2) if it were not for the gravitational force of the Earth pulling it into orbit. In fact, a satellite is falling (acceleration toward Earth), but its high tangensial speed keeps it from hitting Earth. HOME

28. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: PENDAHULUAN • Figure E-2. A moving satellite “falls” out of a straight-line path toward the Earth HOME NEXT

29. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: There is velocity that caused sentrifugal acceleration PENDAHULUAN HOME NEXT

30. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: 9.Weighlessness means there is not gravity. PENDAHULUAN • No matter where an object be there so it will feel the gravitational force. That caused an object weighlessness is its mass. • We know that from this equation: where g is not zero (g ≠ 0). We can get two concluation, those are: • If the mass is zero (m = 0), so the gravitational forse is zero too. • If the mass is not zero (m ≠ 0), so the gravitational force is not zero too. HOME NEXT

31. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: There is no such thing as zero gravity. The reach of gravity is infinite - you are even affected by the smallest rock in the farthest galaxy by 0.0000000000000000000000001 newtons. Weightlessness is a feeling: generally when you are in free-fall because you are in geosynchronous orbit, you are always falling just back into the loop. Astronauts in space feel the reduction in gravity and if they are not in orbit would feel differing pulls from different directions when they move to different locations. PENDAHULUAN HOME NEXT

32. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: PENDAHULUAN • Between the Earth and the Moon there is a point called the Lagrange point: it's the distance from both the Earth and the Moon that their pulls are equal. At this point you would 'float' forever, at least until another body comes near and adds it's gravity to the mix. HOME NEXT

33. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: 10. The Earth’s spinning motion causes gravity. PENDAHULUAN The gravitational force can be caused by interaction between two mass. The that interaction can be caused and make the gravity. HOME

34. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: Interaction of gravitons of two bodies causes attraction causing gravitational force. PENDAHULUAN HOME NEXT

35. The magnitude of moon velocity can be found by Second Newton’s Laws. There are: THANK YOU FOR YOUR ATTENTION SEE YOU ……. PENDAHULUAN