Question

water is drawn from a well in a bucket tied to the end of a rope whose other end wraps around a cylinder of mass 50 kg and diameter 25 cm. as you turn this cylinder with a crank, the rope raises the bucket. if the mass of a bucket of water is 20 kg, what torque must you apply to the crank to raise the bucket of water at a constant speed?

Answer 1

m_c (mass of cylinder)=50 kg

d=25 cm so r=12.5 cm = 0.125 m m_b

(mass of bucket)=20 kg

So using the equations: RT = � = I � RT= I � (m_b)g-T= (m_b)aR And from what I understand, this is the same as the tangential acceleration? (m_b)g-T=(m_b) � r = F T= ( i � ) / r (m_b)g -(( i � ) / r ) = m � r � ( ((m_b)r) + (I /R ) ) = (m_b)g Leaving us with the final : � = ((m_b)g)/(((m_b)r) + (I /r)) Using this equation, I found I = 0.390625 and the final answer would be 35 rad/s^2 Sorry for such a long post--this is my first time on the website and I read the rules so hopefully I've done everything correctly! Thank you all!

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