Gravitational force & escape velocity

Thread starter hadeel
Start date Sep 21, 2012
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Escape Escape velocity Force Gravitational Gravitational force Velocity

AI Thread Summary

The gravitational force is described by the equation F = mk/r^2, where the negative value of k indicates that gravity is an attractive force acting in the negative radial direction. For escape velocity, the initial velocity can be derived as v(initial) = √(2gR), which can be proven using the principle of conservation of energy. This relationship shows that the kinetic energy required to escape a gravitational field is equal to the gravitational potential energy at that distance. Understanding these concepts is crucial for grasping the fundamentals of gravitational interactions and escape dynamics. The discussion emphasizes the mathematical foundations of gravitational force and escape velocity.

Sep 21, 2012

hadeel

1- F = mk/r^2 ... k is -ve value ...why ?? please in concise way

2- for escape velocity ...
v( inital) = root ( 2gR )... with proof

thank u

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Sep 21, 2012

Doc Al

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hadeel said:

1- F = mk/r^2 ... k is -ve value ...why ?? please in concise way

Gravity is an attractive force, which acts in the -r direction.

2- for escape velocity ...
v( inital) = root ( 2gR )... with proof

Prove it for yourself using conservation of energy.

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