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a football is kicked at an angle θ with respect to the horizontal. which one of the following statements best describes the acceleration of the football during this event if air resistance is neglected?
the acceleration is zero m/s² when the football has reached the highest point in its trajectory.
the acceleration is zero m/s² at all times.
the acceleration starts at 9.8 m/s² and drops to some constant lower value as the ball approaches the ground.
the acceleration is positive as the football rises, and it is negative as the football falls.
the acceleration is 9.8 m/s² at all times.

Explanation:

Step1: Analyze motion under gravity

When air - resistance is neglected, the only force acting on the football is the gravitational force.

Step2: Recall gravitational acceleration value

The acceleration due to gravity near the Earth's surface is approximately $g = 9.8\ m/s^{2}$ and it acts downwards throughout the motion of the projectile (the football). Whether the football is rising, at its highest point, or falling, the acceleration remains $9.8\ m/s^{2}$ downwards.

Answer:

The acceleration is 9.8 m/s² at all times.