Question

iii) When a spacecraft is launched into outer space, the velocity attained by it should be great than the escape velocity.why?​

Answer 1

Escape velocity :- it is the velocity of an object required to escape the gravitational field of Earth.

when a spacecraft is launched into space it's velocity must be greater than the escape velocity because the size of rocket is too big so there is much gravitational force on it and the other forces like friction due to air are also works on it which slow down its velocity so to maintain the velocity and go to space it's velocity must be greater than the escape velocity of earth.