Projectile Motion Problem. Is my answer correct ?

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The discussion revolves around a projectile motion problem involving a launch from point A to point B, navigating around a pole of height H on a double inclined plane. The user derived a formula for the height h using the angles of the inclines and the distance D. They then expressed the angle of launch φ in terms of the time to collide with the pole and the other parameters. The inquiry seeks validation of their solution and asks for conditions related to projectile motion before reaching maximum and minimum heights. The response emphasizes the need for the answer to incorporate initial velocity (V0), incline angles (α and β), and the height of the pole (H).
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Homework Statement


A projectile is to be launched so as to go from A to B [which are respectively at the bases of a double inclined plane having angles \alpha and \beta as seen in the figure] and just barely miss a pole of height H that is located at the tip. If the distance between A and B is D, find the angle with the horizontal at which the projectile should be launched.

[PLAIN]http://b1111.hizliresim.com/r/k/llf5.jpg

The Attempt at a Solution


[PLAIN]http://b1111.hizliresim.com/r/k/llds.jpg

I found h=\frac{D\tan\alpha\tan\beta}{\tan\alpha+\tan\beta}

and I considered a particle which is at B is falling free.And Vo vector aimed to point B when t=0 , so they must collide at t=t_{collide} and at top of the H.
Then i wrote \tan\phi=\frac{1/2gt_{collide}^2+H+h}{\frac{D\tan\beta}{\tan\alpha+\tan\beta}}
and i found
\phi= \tan^-1(\frac{(1/2gt_{collide}^2+H)(\tan\alpha+\tan\beta)+D\tan \alpha \tan\beta}{D\tan\beta})

Is my answer is correct ? and are there any solutions for conditions which are before reaching maximum height and minumum height ?
 
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Your "answer" assumes you know the the time it will take the projectile to reach the top of the pole.

The answer should be a function of the initial velocity (V0), the angles of the inclines (α and β), and the height of the pole from the top of the incline (H).
 
Did you find an answer?
 
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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