After a fall, a 77 kg rock climber finds himself dangling from the end of a rope that had been 15 m long and 9.1 mm in diameter but has stretched by 2.3 cm. For the rope, calculate (a) the strain, (b) the stress, and (c) the Young's modulus. strain = ΔL/L stress = F/A Young's modulus = (F/A)/(ΔL/L) I haven't gotten any of these right and I have no idea what I'm doing wrong on them. a) 2.3 cm = .023 m / 15 m = .0015 b) A = ∏r2 = (∏)(.0091/2)2 = 6.503E-5 m2 stress = ((77)(9.8))/(6.503E-5) = 1.16E7 N/m2 c) (754.6/6.503E-5) / (.023/15) = .756 None of those were right; also I thought Young's modulus was supposed to be a huge number so obviously that's not right. Any help is appreciated!