1.Disk A of constant thicness and is at rest when it is placed in contact with belt BC, which moves with constant velocity v. Denoting by uk the coefficient of kinetic fr4iction between the disk and the belt. derive an expression for number of rev executed by t he disk before it attains a constant angular velocity.
2.A 39 ft length of railroad rail of weight 44 lb/ft is lifted by the tongs shown. Determine the force exerted at D and E on tong BDF.
3.How many truckloads of trucks hauling an average volumeof 6 LCY (4.6 LCM) would be required to haul 1 million CCY (764, 600 CCM) of gravel to a dam site?