What is the magnitude of the impulse imparted by a kicked ball to the foot?

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The discussion focuses on calculating the impulse imparted by a kicked ball to the foot, with a mass of 0.4 kg and a final speed of 5.0 m/s at a 60-degree angle. The impulse is determined using the formula I = change(p) = mvf - mvi, resulting in an impulse of 1 N*s. Participants express confusion about the relevance of the angle in the calculation, with one confirming that the angle does not affect the impulse value. The conversation includes a light-hearted exchange about coincidentally posting similar problems. Ultimately, the correct impulse calculation is confirmed to be 1 N*s, regardless of the angle.
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Homework Statement


A ball of mass 0.4 kg is initially at rest on the
ground. It is kicked and leaves the kicker’s
foot with a speed of 5.0 m/s in a direction 60◦
above the horizontal.
The magnitude of the impulse k~Ik imparted
by the ball to the foot is most nearly



The Attempt at a Solution



I=change(p)
pf-pi
mvf-mvi
(0.4)(5cos60)-(0.4)(0)
=1 N*s
Where did I go wrong in the problem?
 
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WOW how weird we posted the same problem near the same time as each other o_O

Do you go to Bellaire by any chance?

(BTW check my topic, I'm not sure I'm right but I did it differently than you)
 


Ha, that's really weird. No, I go to Connally. I don't know if the angle would matter or if it just would be the velocity itself. I got it wrong when I did it.
 


Ok, I was right, just ignore the angle :D
 


Ok, thanks!
 
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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