Height of ball bounce with air resistance

AI Thread Summary
The discussion focuses on calculating the height a ball will bounce after being dropped from a 30 m building, considering air resistance. The air resistance is quantified using a specific equation involving parameters like drag coefficient, surface area, air density, and velocity. The solution provided indicates that the ball will bounce to a height of 9.15 m if the collision is elastic. The original poster expresses interest in alternative methods for solving the problem, particularly through kinematic and potential energy equations, but doubts their applicability due to the velocity-dependent nature of air resistance. Ultimately, the consensus is that differential equations are necessary to accurately account for the effects of air resistance on the ball's motion.
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Homework Statement


Ball with mass of 0.7 kg and radius 0.15 m is dropped from top of the building 30 m tall. Force of air resistance which acts on ball is given with the equation:

F_r = \frac{1}{2} c S ρ v^2

where
c = 0.5
S = r^2 ∏
ρ = 1.29 \frac{kg}{m^3}
v = current speed.

How tall will ball bounce of the ground if we suppose that collision was
elastic?

(Ans: h = 9.15 m)

Homework Equations


Given above.

The Attempt at a Solution


I have solved this with differential equations of motions(which took me quite a lot
of time integrating...) but I'm interested whether this can be solved with equations
for kinematic and potential energy and how?
 
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I don't think so, since energy dissipated by air friction is a function of v and you don't know v unless you solve the diff. eq.
 
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