What impact does air resistance have on a ball thrown upward with speed x?

AI Thread Summary
When a ball is thrown upward with speed x, it returns at the same speed in the absence of air resistance due to conservation of energy. In contrast, when air resistance is present, the ball descends at a slower speed and with reduced kinetic energy. The energy lost during the ascent and descent is transformed into heat due to friction with the air. Factors such as the ball's surface texture, temperature, and humidity influence the amount of energy lost. Overall, air resistance significantly affects the ball's return speed and energy dynamics.
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if we throw upward a ball with speed x. What can we say about it when the ball returns in the presence of air resistance? What about in the absence?
 
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itsme1 said:
if we throw upward a ball with speed x. What can we say about it when the ball returns in the presence of air resistance? What about in the absence?

In the absence of air resistance, it's easy - the ball comes back down at the same speed that it went up with. This follows from conservation of energy; the ball started with a certain amount of kinetic energy, traded the kinetic energy for potential energy as it climbed, and then reversed the trade and regained the kinetic energy on the way down.

In the presence of air resistance, the ball will come down at a slower speed and with less kinetic energy than it started with. The missing energy will have gone into friction with the air heating the ball and the air around it; the exact amount of energy lost will depend on many variables (the texture of the surface of the ball, the temperature and humidity, ...) and is generally hard to calculate.
 
That sounds like homework
 
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