# physics

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A 4.0 kg pulley of radius 0.15 m is pivoted about an axis through its center. What constant torque is required for the pulley to reach an angular speed of 25 rad/s after rotating 6.0 revolutions, starting from rest?

• physics -

Torque=momentinertia*anglular acceleration

Torque= I * angacc

but

wf^2=wi^2+2*angacc*displacement

wf^2=wi^2+2*angacc*revolutions*2PI

solve for angacc, then torque

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