Acasting weighing 3 tonnes is to be hauled by a winch, along a factory floor at a constant velocity of 10 m/min. i)- if the winch exerts a pull of 10kn determine the coefficient of friction between the casting and the factory floor? ii) if 1 tonne of componentry is now attached to the casting, how much force must be exerted by the winch to move the casting back to position at the same velocity? iii)-if the velocity required to move the casting is reduced to 8 m/min, what pulling force is now required? iv) what power ratings are required