Question

Two persons pull a rope towards themselves. Each person exerts a force of $100$N on the rope. Find the Young modulus of the material of the rope if it extends in length by $1$cm. (Original length of the rope $=2$m and the area of cross section $=2$ $c{m}^2$).

Answer 1

$Y=\frac{Fl}{A△l}$

$F=2\times 100=200N$

$l=1m$

$△l=0.01m$

$A=2\times {10}^{-4}{m}^2$

$Y=\frac{200\times 1}{2\times {10}^{-4}\times 0.01}$

$Y={10}^{8}N{m}^{-2}$