How Is Maximum Force Calculated from Impulse in a Bouncing Ball Scenario?

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To calculate the maximum force exerted by the floor on a bouncing ball, the change in momentum (dP) is determined by the velocities just before and after impact. The ball, weighing 200 g, hits the ground at -6.10 m/s and rebounds at 5.42 m/s, resulting in a total change in velocity (dv) of 11.52 m/s. Using the momentum equation, dP is calculated as 2.304 kg·m/s. The maximum force (F_max) can then be derived from the impulse, represented as the area under the force-time curve, leading to the equation F_max = 2*(p2 - p1)/0.005 s. This approach effectively connects impulse and maximum force in the context of the bouncing ball scenario.
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Homework Statement



A 200 g ball is dropped from a height of 1.9 m, bounces on a hard floor, and rebounds to a height of 1.5 m. The figure shows the impulse received from the floor.
What maximum force does the floor exert on the ball?

09.P29.jpg


Homework Equations



Kinetics:
x-xo = vot + 0.5at2
v2 = v02 + 2a(x - xo)
v = vo + at

Momentum and Force:
SF*dt = dP = m*dv

The Attempt at a Solution



What I did was calculate the velocity of the ball just as it hit the ground (-6.10m/s) and just as it rebounded (5.42m/s).
Then, using these I found the dv (5.42 + 6.10 = 11.52m/s) and plugged that into the momentum equation:
dP = m * dv
dP = 0.2 * 11.52 = 2.304 = SFdt

From here I don't know how to calculate the maximum force, as I know virtually nothing about integrals. Also, my work so far is probably wrong somewhere so some help would be greatly appreciated! :)
 
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I'm in mechanics and i have not seen a question about max force. But i'll try this. From the graph we can see the Impulse which is the area under the curve is (1/2)(0.005s)F_max
This is equal to the change in momentum which we can calculate.

So F_max = 2*(p2-p1)/0.005

Where p2-p1 = m(v2-v1)
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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