a ball is thrown vertically into the air because of air resistance its speed when it returns to its staring level compared to it initial speed is what?
If it lost energy due to friction, the returning KE must be less than it left with.
To answer this question, we need to understand the effect of air resistance on the motion of the ball.
When a ball is thrown vertically into the air, it experiences two main forces: gravity pulling it downward and air resistance acting opposite to its direction of motion. Initially, while the ball is moving upward, the force of air resistance opposes its motion and gradually slows it down. At the highest point of its trajectory, the ball momentarily comes to a stop and starts to fall back down due to gravity.
As the ball descends, the force of gravity accelerates it, causing it to gain speed. However, unlike during the upward motion, the force of air resistance now aids the ball's motion and acts in the same direction, opposing the force of gravity. This results in a decreased net force and a slower acceleration compared to a motion without air resistance.
Due to the opposing force of air resistance during the upward and downward motions, the ball will return to its starting level with a lower speed than its initial speed. In essence, air resistance acts as a 'drag' force, reducing the ball's speed. Therefore, the speed of the ball when it returns to its starting level will be less than its initial speed.