Help!!!, please help me this physic question?

A projectile is an example of a free falling body where we assume that only the force of gravity affects its motion. This means that its acceleration is due to the force of gravity which is 9.8 m/s^2 downward.

At its highest point, before and after reaching the highest point the acceleration is still 9.8 m/s^2 downward.

Yes, it's possible. A projectile projected at angle above the horizontal will have only its horizontal component when it reaches its maximum height. At this point the acceleration due to gravity is directed downward perpendicular to the horizontal velocity of the projectile.

Hope this helps.

teddy boy

At the top of the trajectory it is zero. As it nears the top it is approaching zero (losing velocity). As it moves away it is leaving zero (gaining velocity).
Yes,if the projectile is fire out into space forming a perfect circular orbit around earth or some Satellite. The acceleration will be toward the body it is orbiting and the velocity will be at a right angle to the acceleration.

velocity is zero, it is going neither up nor down. Acceleration towards the earth due to gravity is constant. The projectile has no energy source of it's own.

Acceleration is the rate of change of velocity. So it is decelerating as it goes up, then accelerating again as gravity pulls it towards the Earth. The size and sign of the acceleration is the same, -9.8m/s/s. It has a velocity parallel to the Earth's surface, if it was initially shot out at anything other than 90 degrees to that surface.

An example would be a cannon ball fired at an angle of 45 degrees to the Earth's surface. It would travel furthest that at any other angle as the energy put into it would be divided equally between giving it altitude and horizontal velocity.

acceleration is constant
gravity is -9.81 m/s downward