pulley system

There are three main factors that affect the efficiency of a pulley system. The first one is friction on the axle of the pulley. The second factor is the mass of the pulley. A heavy pulley absorbs more energy when revolving, thus reducing the useful energy output and lowering the efficiency. The last factor is the diameter of the pulley. A pulley with long diameter possesses high moment of inertia, which needs more energy to revolve than one with short diameter.

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