Q6 of 8 Page 178

The speed of a motor increases from 1200rpm to 1800rpm in 20s. How many revolutions does it make in this period of time?

Initial angular velocity =


Final angular velocity =


Time = t = 20s







If is the angular acceleration, then using



We get,





If θ = the no. of rotations


Then using,





Revolutions made in 10 s = 500


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