Will a Ball Take Longer To Rise or Fall?

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SUMMARY

The discussion centers on the dynamics of a ball thrown vertically upward, specifically comparing the time taken for the ball to rise to its maximum height versus the time taken to fall back to its original position. Participants assert that air friction and gravitational force (mg) act against the ball's motion during ascent, while only air friction opposes the motion during descent. The consensus indicates that despite the differing forces, the time taken for ascent and descent remains equal due to the symmetrical nature of projectile motion under uniform gravitational acceleration.

PREREQUISITES
  • Understanding of Newton's laws of motion
  • Basic knowledge of forces, specifically gravitational force (mg) and air friction (Ff)
  • Familiarity with kinematic equations for uniformly accelerated motion
  • Concept of net force and its application in motion analysis
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  • Study the effects of air resistance on projectile motion
  • Learn about the kinematic equations for vertical motion
  • Explore the concept of terminal velocity and its implications
  • Investigate real-world applications of projectile motion in sports physics
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Physics students, educators, and anyone interested in understanding the principles of motion and forces acting on objects in free fall.

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if I threw a ball straight up (including air friction), would it take longer for the ball to drop back to its original position from its max height or longer for the ball to rise up to its max height?

here's what I'm thinking, on the way up, there is air friction and mg going agaist the initial velocity, on the way down, it would just be air friction against the ball. Since on the way down, there is only one resistive force, then it would fall faster right?

also, air friction in this problem decreases the acceleration right?
 
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here's what I'm thinking, on the way up, there is air friction and mg going agaist the initial velocity, on the way down, it would just be air friction against the ball. Since on the way down, there is only one resistive force, then it would fall faster right?

So mg doesn't act on the way down? Are you sure?
 
the resistive force on the way up would be F=Fg+Ff

on the way down it would be F=Ff

since there is less resistive force on the way down, the ball would drop faster
 
Net force on the way up, with up as positive:

-(F_g + F_a)

Down:

-F_g + F_a

Finding:

-F_g - F_a (?) -F_g + F_a

Cancel -F_g

-F_a (?) F_a

F_a is acting AGAINST the direction of motion in both directions. It's still my opinion that it takes the same time to go up and down.
 

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