CBSE Class 9 Answered

yes  but not permanently ,only momentarily. To explain, say that u throw a ball at velocity u upwards , the earth's acceleration is -g. consider t=0 at the moment of throwing. u+(-g)T is the velocity of the ball at any instant t (after throwing). At the time t=u/(+g) we have the ball's velocity 0 but the ball persistently has -g acceleration all along duration of flight until it hits ground . Its because the object has (-g) acceleration even at velocity 0 that the ball starts falling and finally comes down to hit the ground