A steel cable is used to support an elevator cage at the bottom of a 2400-ft-deep mineshaft. A uniform normal strain of 300 μin./in. is produced in the cable by the weight of the cage. At each point, the weight of the cable produces an additional normal strain that is proportional to the length of the cable below the point. Assume D = 2400 ft and d = 200 ft. If the total normal strain in the cable at the cable drum (upper end of the cable) is 620 uin./in., determine (a) the strain in the cable at a depth of 200 ft. (b) the total elongation of the cable. Drum Answers: (a) Cable + ε = i Elevator cage D X uin./in.

The term strain indicates the variation in an object's length, area, and volume when the object is subjected to an external force. The external force may be of normal, shear, moment, torque, etc. The strain in an object depends on the types of external f…