Final answer:
The ball was in the air for about 4.08 seconds. When caught, the ball's speed was the same as its initial throw speed of 20 m/s, but in the downward direction.
Step-by-step explanation:
Tony throws a baseball straight up with a velocity of 20 m/s, and catches it at the same level. To determine how long the ball was in the air, we can use the kinematic equation for vertically accelerated motion assuming acceleration due to gravity is 9.8 m/s2 directed downwards and initial velocity is upward, making it effectively negative.
The time of flight t is given by t = 2 * (V0 / g), where V0 is the initial velocity and g is the acceleration due to gravity. This calculation yields t = 2 * (20 m/s / 9.8 m/s2) ≈ 4.08 s.
When Tony catches the ball, the speed of the ball is the same as the speed at which it was thrown, 20 m/s, but in the opposite direction (downwards), as there is no air resistance to alter the speed (only the direction of motion changes due to gravity).