A thick uniform rubber rope of density 1.5gcm−3 and Young’s modulus 5×106Nm−7 has a length of 8m. When hung from the ceiling of a room, the increase in length of the rope due to its own weight will be
9.6 × 10−2m
Y=FAIL=FLAl=(ρAL)gL2Al=ρgL22l⇒I=ρgL22YI=1.5×103×822×5×106=9.6×10−2m