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11 Cards in this Set
- Front
- Back
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the general gravitational law
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a body on the universe attracts another body by a force directly proportional to the product of their masses and inversely proportional to square the distance between them.
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Gravitational field
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the space where the gravitational forces appear
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the gravitational field intensity
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the gravitational forces acting on a body of mass 1kg
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Equation of gravitational force intensity:
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¤If a body is at HEIGHT above earth
¤If a body is at DEPTH below earth |
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A satellite:
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an object projected at a a certain velocity to rotate in a roughly circular path at a constant distance from the earth's surface
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orbital velocity
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the velocity that makes the satellite orbit the earth and rotate in a roughly circular path at a constant distance from earth's surface.
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what happens when the satellite stops and the velocity becomes zero
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it will move in a straight line and fall on earth surface
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what happens when the gravitational force dissapears
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the satellite will move in a straight line tangential of the circular path away from earth.
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how to calculate the time take for one revolution around earth
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circumfrance ÷ speed
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Importance of a satellite:
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¤communication: tv transmission, radio transmission, internet, phone calls
¤astronomical : huge telescopes ¤remote sensing: study emigrant birds , determine mineral sources. ¤explanatory: used by military and political leaders to make decisions ¤meteorological |
