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circular motion - are answers wrong or (1 Viewer)

anonymoushehe

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i get the working out for the worked solutions, but why is my answer still wrong? I calculated the centirpetal force first and then equated it to F L sin 60 since the horizontal component of the lift force is contributing to the centripetal force? or am i wrong??

Screenshot 2024-11-29 at 3.40.17 pm.pngScreenshot 2024-11-29 at 3.43.32 pm.pngIMG_0797.jpg
 

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C2H6O

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i get the working out for the worked solutions, but why is my answer still wrong? I calculated the centirpetal force first and then equated it to F L sin 60 since the horizontal component of the lift force is contributing to the centripetal force? or am i wrong??

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Hmm i feel like for part b you shouldn't even need to consider centripetal force. As shown in the solutions it's just a simple trig problem right? The vertical component of force lift balances with force weight, so just equate the 2 and solve for force lift.
 

anonymoushehe

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Hmm i feel like for part b you shouldn't even need to consider centripetal force. As shown in the solutions it's just a simple trig problem right? The vertical component of force lift balances with force weight, so just equate the 2 and solve for force lift.
that was what i was thinking, but shouldnt either method be fine?
 

C2H6O

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that was what i was thinking, but shouldnt either method be fine?
Ohh I get what you mean now. Yeah both should work. I reversed the calculations and found that for an airplane with this mass and this speed flying in a circle with that radius you would need to have a tilt of 21.04 degrees, which contradicts part b. So i guess they didn't consider ppl would try this other method, although it is a pretty bad flaw in the question.
 

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