Solving Basketball Parabola Puzzle: Initial Velocity at 35°

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A basketball player throws a ball from a height of 2m at a 35-degree angle towards a basket 9.5m away and 3.1m high. The initial attempt to calculate the initial velocity yielded 4.64 m/s, but the textbook states the correct initial velocity is 11 m/s. The discrepancy arises from the need to solve two equations, one for vertical motion and one for horizontal motion, rather than relying solely on the maximum height assumption. The maximum height of 1.1m is questioned since the ball starts at 2m. Clarification from the teacher is pending to resolve the misunderstanding.
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Homework Statement



A basketball player is standing 9.5 m from the basket, which is at a height of 3.1m. she throws the ball from a initial height of 2m at an angle of 35 degrees above the horizontal. The ball goes through the basket. Determine intial velocity.

PS Assume the max height of the parabola of the ball is 1.1 m.

Homework Equations



Dont know

The Attempt at a Solution



I took only half the parabola diagram and assumed v2 is 0 m/s

Vert

v1 = ?
v2 = 0 m/s
a = -9.8 m/s^2
max height = 1.1 m

I used the equation

v2^2 = v1^2 + 2ad

and got v1 as 4.64 m/s and from there on on I found initial velocity at an angle.

BUT the textbook gives a different answer (11m/s) as the initial velocity at an angle.

I can't figure out why I'm getting this wrong and my teacher sasys she will come back to me as she can't figure the mistake in mine... so help LOL
 
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Not sure why you need to assume the max height of the parabola is 1.1m. It is already starting out at 2m.

The textbook answer of 11m/s can be obtained by solving a system of 2 equations- one describing the motion in the y-axis and the other for the x-axis.
 
Last edited:
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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