Physics
Mechanics
Easy
Question
A missile is launched with a velocity less than the escape velocity. The sum of its kinetic and potential energy is
- Negative
- Zero
- May be positive or negative depending upon its initial velocity
The correct answer is: Negative
If missile launched with escape velocity then it will escape from the gravitational field and at infinity its total energy becomes zero.
But if the velocity of projection is less than escape velocity then sum of energies will be negative. This shows that attractive force is working on the satellite.
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