A 90 cm pulley transmits 75 kW at 750 rpm. The arc of contact between the belt and pulley is 135 degrees, the coefficient of friction between belt and pulley is 0.25 and the safe working stress of the belt is 2200 kPa. It is required to find the tangential force at the rim of the pulley in Newton; the effective belt pull in Newton and the width of the belt used if its thickness is 5mm.

A sled of mass 500kg sits at rest on a rough slope that is inclined at 10* to the horizontal. The coefficient of friction between the slope and the sled is 0.3. The sled is held in place by a wire attached to a winch. The tension in the wire is TN. a) Find the maximum possible value of T.   A load of mass mkg is added to the sled, and tension in the wire is increased to 5000N in order to pull the sled and load up the slop. Given that the sled and load are pulled a distance of 100m in 80seconds, b) Work out the value of m

An inclined plane at an angle of 15o is used to lift a 250 kg sofa through a vertical height of 5 meters.  If the coefficient of kinetic friction is 0.12, what is the Mechanical Advantage, Ideal Mechanical Advantage, and efficiency of the plane?