If the wire of length 50cm elongater by 0.1 mm the strain is

What mass must by suspended from free end of steel wire of length 2m and diameter 1 mm to stretch it by 1 mm ? (Y = 2 xx 10^11 N/m^2,g = 9.8m/s^2)

A steel wire of length 1 m and diameter 0.2mm is elongated by 1mm due to a weight of 3.14kg. The Young's modulus of steel wire is