Question

Many caterpillars construct cocoons from silk, one of the strongest naturally occurring materials known. Each thread is typically 2.0 um in diameter, and the silk has a Young's modulus of 4.0 x 109 N/m2 Assuming that there is no appreciable space between the N =1087222 strands parallel strands, how many strands N would be needed to make a rope 8.0 m long that would stretch only 1.06 cm when supporting a pair of 87-kg mountain climbers? Again assuming that there is no appreciable space between d = cm the parallel strands, what would be the diameter d of the rope?

Answer 1

formua for yourg's madulus, FI = h AC D) 4fl Te2 (DL) T(ai6)Co0106) C4x10) -665X16 4(8) N=을= a(87)(9~8) 1665x10-5 0a4 10SHand A10a4x10 x)( (1-oa4 k10 ч D=(1004 X10)d D = ( MON9I0)d=1019x10 (an0 a 0al m