A 5-ton elevator is supported by a standard steel cable of 2.5-in.2 cross section and an effective modulus of elasticity of 12 x 106 psi. As the elevator is descending at a constant 400 ft/min, an accident causes the top of the cable, 70 ft above the elevator, to stop suddenly. Estimate the maximum elongation and maximum tensile stress developed in the cable (see Figure P7.12).
