Question

A particle on earth's surface is given a velocity equal to its escape velocity. Its total mechanical energy will be

• A. Negative
• B. Positive
• C. Zero
• D. Infinite

Answer 1

The correct option is C

Zero

On earth's surface potential energy of particle is

U =$-\frac{GMm}{R}$

and kinetic energy at a velocity equal to its escape velocity is

$K=\frac{GMm}{R}$

i.e., K + U = 0

or total mechanical energy is zero.