KB) *2-28. The material distorts into the dashed position shown. Determine the average normal strain that occurs along the diagonals AD and CF. 2-31. The curved pipe has an original radius of 2 ft. If it is heated nonuniformly, so that the normal strain along its length is = 0.05 cos 0, determine the increase in length of the pipe. 25 mm y 10 mm CH 15 mm D 100 mm B 18Q A 80 mm Probs. 2-27/28 50 mm 2 ft x Probs. 2-31/32