"An object experiences a net zero external unbalanced force. Is it possible for the object to be travelling with a non-zero velocity?If yes, state the conditions that must be placed on the magnitude and direction of the velocity.If no, provide a reason."
Sri. RAZIMAN T.V. gives the explanation.
" It is possible that the object has a non zero velocity.Look at the statement of Newtons First law :An object remains in its state of rest or motion with uniform velocity unless acted upon by an external unbalanced force".So in the absence of a net external force, the object remains moving with whatever its initial velocity was and this may be non-zero.There are absolutely no conditions on the magnitude or direction of this initial velocity (apart from the obvious relativistic constraint v less than c)