Does Air Resistance Cause a Ball to Take Longer Falling Down Than Rising Up?

AI Thread Summary
When a ball is thrown upwards and then falls back down, air resistance affects the time taken for each phase of motion. It is generally accepted that the ball takes longer to fall back down due to the opposing force of air resistance acting against gravity. The initial upward motion is aided by the force applied during the throw, but once released, the ball only has its initial velocity and is subject to gravitational pull and air resistance. The discussion highlights the importance of understanding kinematic equations and the role of terminal velocity in this context. Overall, air resistance significantly influences the descent time compared to the ascent.
yoyo16
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Homework Statement



If a ball is thrown upwards and lands in the same spot, would it take longer to reach max height or drop back down from the max height? Also use air resistance.

Homework Equations





The Attempt at a Solution



I believe that it would take longer for the object to fall back down. I think it is because that when throwing a ball upwards, gravity would be positive and for ex. if a ball was thrown with acceleration of 2m/s^2, you would add two to 9.8 which would help the ball go up faster while when falling down, the ball air resistance would be in the opposite direction causing the ball to fall back slowly. I'm not sure how to explain my answer properly. This is what I understand so far, if I'm not correct can someone please explain this too me.

Thanks,
 
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You are not correct.

First of all let's assume air resistance is a function of velocity and it creates a drag force in the opposite direction of motion.

Second, you can't throw anything with an acceleration once it leaves your hand. You can only accelerate it over the time your hand can continue to exert a force on it. Once it leaves your hand it will only have an initial velocity.

Do you know the kinematic equations of motion?
 
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Yes. How would you use that when explaining the answer for this question?
 
yoyo16 said:
Yes. How would you use that when explaining the answer for this question?
I doubt that you will be able to account for your answer mathematically without resorting to the use of caculus. (By the way, air resistance always acts to oppose the motion.)

But perhaps you should ponder an extreme example. (Hint: terminal velocity)
 
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