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We derive the formula of escape velocity by using conservation of mechanical energy, where we consider that work done by external force is neglected. But to provide the velocity to send an object to infinite distance from gravitational pull of Earth, don't we have to apply an external force?

User Caheem
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Final answer:

The escape velocity from the surface of the Earth is derived using conservation of energy and does not require the application of an external force.

Step-by-step explanation:

In order to provide the velocity to send an object to an infinite distance and escape the gravitational pull of the Earth, we do not need to apply an external force. Instead, we rely on the object's initial velocity and conservation of mechanical energy.

The formula for escape velocity is derived by setting the total energy of the object equal to zero. This means that the kinetic energy at the surface of the Earth is equal to the negative of the gravitational potential energy at infinity.

By solving for the escape velocity using these energy considerations, we find that it is possible to escape the gravitational pull of the Earth without the need for an external force.

User JackRed
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