A dad pushes tangentially on a small hand-driven merry-go-round and is able to accelerate it from rest to a frequency of 18 rpm,
1 answer:
Answer:
F = 176.175 N
Explanation:
given,
radius of merry - go - round = 2.7 m
mass of the disk = 800 kg
speed of the merry- go-round = 18 rpm
= 18
= 1.88 rad/s
time = 13 s
mass of two children = 25 kg
ω = ω₀ + α t
1.88 = 0 + α(13)
α = 0.145 rad/s²
we know
τ = I α
so,
τ = I α
τ = 3280.5 x 0.145
τ = 475.67 N m
τ = F x r
475.67 = F x 2.7
F = 176.175 N
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We know from the problem both maximum velocity and maximum acceleration:
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(1)
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while the amplitude is (using (1)):
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(b) We found in the previous step that the angular frequency of the motion is
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