Impulse basketball homework Question

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The discussion revolves around a physics homework problem involving the impulse delivered to a basketball during a bounce pass. The player throws a 0.60 kg basketball at 6.5 m/s at a 64° angle from the vertical, and the task is to calculate the impulse from the floor upon rebound. The initial attempts at calculating impulse using momentum equations were incorrect, indicating confusion about the components of velocity. Key concepts highlighted include the relationship between impulse and momentum, emphasizing that impulse equals the change in momentum during collisions. Understanding these principles is crucial for solving the problem accurately.
creative_wind
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Hello,
I am (obviously) new to the forum. I am in an introductory-level physics course in university and although I had taken a year of physics in high school, these easy intro questions on my homework keep snagging me. This is online homework and I get 5 attempts at the correct solutions. This is what I have:

Homework Statement



To make a bounce pass, a player throws a 0.60 kg basketball toward the floor. The ball hits the floor with a speed of 6.5 m/s at an angle of 64° from the vertical. If the ball rebounds with the same speed and angle, what was the impulse delivered to it by the floor?


Homework Equations


I=Favg(T2-T1)=P=m*v

Where P=momentum


The Attempt at a Solution



I=m*v
m=0.6kg
v=6.5*cos(64)=2.85m/s
I=0.6kg*2.85m/s=1.71kg*m/s <--this was wrong

I=m*v
m=0.6*cos(64)=0.26kg
v=6.5*cos(64)=2.85m/s
I=0.26kg*2.85m/s=0.74kg*m/s <--this was wrong

I figured the velocity had to be in the y-component since it is vertically upward from the floor. I'm really not sure though...

Thanks :)
 
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this should help ya:

Impulse is the integral of force over time, it is measured in Newton-seconds. For instance a force of one Newton applied over one second will change the momentum, a force of two Newton's applied over half of a second will have a similar effect.

For rigid body collisions we take this to its limit and apply an infinite force over an infinitesimally small time. This impulse is equal to the change in momentum of the colliding objects. Because we are talking about forces here, Newton's third law applies, and the impulse on the colliding objects will be equal and opposite.

impulse = m(vf- vi)
 
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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