| Perhaps I am misinterpreting the information but page 9 of the following link states this: "That’s why an object that has most of its mass located near the axis of rotation will have a much smaller rotational mass than an object of the same mass that has most of its mass located far from that axis. Thus a ball of pizza dough has a smaller rotational mass than the finished pizza. And the bigger the pizza gets, the harder it is to start or stop spinning." "Because an object’s rotational mass depends on how far its mass is from the axis of rotation, changes in the axis of rotation are likely to change its rotational mass. For example,less torque is required to spin a tennis racket about its handle (Fig. 2.1.9a) than to flip the racket head-over-handle (Fig. 2.1.9b). When you spin the tennis racket about its handle, the axis of rotation runs right through the handle so that most of the racket’s mass is fairly close to the axis and the rotational mass is small. When you flip the tennis racket head-over-handle, the axis of rotation runs across the handle so that both the head
and the handle are far away from the axis and the rotational mass is large. The tennis racket’s rotational mass becomes even larger when you hold it in your hand and make it rotate about your shoulder rather than its center of mass (Fig. 2.1.9c)." To me, that would suggest that given the same mass of a crank pulley it would take less torque to spin it if the mass is closer to the axis of rotation (i.e. a smaller diameter pulley).
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