Question

The acceleration of an object is not zero at the top of its flight, because the acceleration of gravity on the object does not change.
True / false

Answer 1

Acceleration is 0 only when the speed of an object is constant, whether it is moving at constant speed (speed>0) or it is stationary (speed=0).

The acceleration of gravity does not always equate to the object being accelerated.
If you leave a pencil on the table it will still be affected by the gravitational acceleration (g) but it will surely have no acceleration since it is stationary relative to the Earth.

When an object is thrown upwards into the air, at the top of its flight there will be a short moment of Infinitesimal proportion in which the speed of the object will be zero and the object will remain stationary relative to the ground as all its kinetic energy becomes converted into potential energy. Since that object's speed is zero in that moment, its acceleration will also be zero while evidently still being affected by the graviational pull.

If what I understood was right, I'd say false.