A 1.2m -long steel rod with a diameter of 0.50cm hangs vertically from the ceiling. An auto engine weighing 4.7kN is hung from the rod. By how much does the rod stretch?

Answer 1

so in my head I am supposed to have stored the Young's modulus of steel ?

delta L/L = tensile stress/E

or delta L = F L /(E A)
F = 4700 N
A = (pi/4) .005^2 meters^2
L = 1.2 meters
E = you look it up

Answer 2

You look it up.