Question

A projectile fired vertically upwards with escape speed of earth,if it is fired as 45° to horixontal and it escape from the earth

Answer 1

Escape velocity is the minimum velocity required for an object to move from Gravitational influence of a massive body .

For example , in case of earth escape velocity , ve :

1/2mve² [ Kinetic energy of body ] = GMm/R [ gravitational potential energy between body and earth ]

ve² = 2GM/R

ve = √{2GM/R} or, √{2gR}

Here you can see that escape velocity of earth = √{2gR} , which is independent from angle of projection.So , escape velocity will be same , when a projectile is fired at 45° to the horizontal .

Answer 2

As we know that Ve(Escape Velocity) doesn't depend upon angle of Projection.

Hence, The Velocity of body will be same i.e. "v".