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How much work is done [in J] when a weight lifter lifts 11:]I kg from 1.5 m to 2.0 m above the ground? [Use 9.8 rn,-'52 for g.) :1 A variable force of 6x72 pounds moves an object along a straight line when it is x feet from the origin Calcuiate the work done (in ft-ib) in moving the object from x : 1 ft to x : 11 ft' (Round your answer to two decimal places.) According to Hooke's Law, the force required to hold the spring stretched x m beyond its natural length is given by x} 2 for, where k is the spring constant. Suppose that 6 J of work is needed to stretch a spring from its natural length of 24 cm to a length of 35 cm. Find the exact value of k, in Nfrn. SW (a) How much work (in J) is needed to stretch the spring from 29- cm to 33 cm? (Round your answer to two decimal places} :1 {b} How far beyond its natural length (in cm} will a force of 50 N keep the spring stretched? [Round your answer one decimal place.) :cm A 10 ft chain weighs 25 lb and hangs from a ceiling. Find theI work clone (in ft-lb} in lifting the lower end of theI chain to the ceiling so that it's level with the upper end. x The table shows va Lies of a force function x} Iwhere X is measured in meters and x,- in newtons. Use the midpoint rule with n = 4 to estimate the work W (in J) done by the force in moving an object from x = 4 to x = 35