Escape Velocity - each other, etc.). Using Newton's laws of...

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Escape Velocity If an object moves fast enough it can escape a massive object's gravity and not be drawn back toward the massive object. The critical speed needed to do this is the escape velocity . More specifically, this is the initial speed something needs to escape the object's gravity and assumes that there is no other force acting on the object besides gravity after the initial boost. Rockets leaving the Earth do not have the escape velocity at the beginning but the engines provide thrust for an extended period of time, so the rockets can eventually escape. The concept of escape velocity applies to anything gravitationally attracted to anything else (gas particles in planet atmospheres, comets orbiting the Sun, light trying to escape from black holes, galaxies orbiting
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Unformatted text preview: each other, etc.). Using Newton's laws of motion and law of gravity, you can find that the escape velocity v esc looks very similar to the orbital speed: v esc = Sqrt [ (2 G M)/r ]. This is a factor Sqrt [2] larger than the circular orbital speed . Since the mass M is on top of the fraction, the escape velocity increases as the mass increases. More massive bodies exert greater gravity force, so escaping objects have to move faster to overcome the greater gravity. Also, the distance from the center of the object r is in the bottom of the fraction, so the escape velocity DEcreases as the distance increases. Gravity decreases with greater distance, so objects farther from a massive body do not need to move as quickly to escape it than those closer to it. Vocabulary...
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Escape Velocity - each other, etc.). Using Newton's laws of...

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