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2 years ago

7

A student of weight 659 N rides a steadily rotating Ferris wheel (the student sits upright). At the highest point, the magnitude

of the normal force F with arrowN on the student from the seat is 560 N. (a) Does the student feel "light" or "heavy" there? heavy light Correct: Your answer is correct. (b)What is the magnitude of F with arrowN at the lowest point? 758 Correct: Your answer is correct. N (c) If the wheel's speed is doubled, what is the magnitude of F with arrowN at the highest point? N (d) What is the magnitude of F with arrowN at the lowest point under the same conditions as in (c)?

1 answer:

Misha Larkins [42]2 years ago

4 0

Answer:

a) The student feel light

b) Nbottom = 758 N

c) N'top= 236 N

d) N'bottom= 1055 N

Explanation:

a) W= 659N , Ntop= 560N

W > Ntop ---> Student feel less weight

b) Top:

∑F= W - Ntop = m.v²/R

m.v²/R = 659N - 560 N = 99 N

Bottom:

∑F= Nbottom- W = m.v²/R

Nbottom= W + m.v²/R = 659N + 99 N = 758N

c) W= 659 N , Ntop= 560 N , v'=2.v

N'top= ?

∑F= W - N'top = m.v'²/R

N'top= W - 4.m.v²/R

N'top = 659 N - 4. 99 N = 263 N

d) N'bottom = ?

∑Fbottom= N'bottom- W = m.v'²/R

N'bottom = W + 4.m.v²/R = 659 N + 4. 99 N = 1055 N

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<u>Answer</u>:

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<u>Explanation</u>:

<u>Given</u>:

Mass of the crate, m = 220 kg

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=> $\theta = Sin^{-1} \frac{d}{L}$ =

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=> $T = \frac{mg}{cos\theta}$

=> $T = \frac{230 \times 9.8 }{cos(19.5)}$

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Wg = Fs.d = - mgh

Wg = - mgL ( 1 - Cosθ )

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= $-230 \times 9.8\times 12 ( 1 - 0.9426) )$

= $-230 \times 9.8\times 12 (0.0574)$

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Here the work done by force is not equal to F*d

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And re-arranging it

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