JEE Advanced 2018 Paper 2

A steel wire of diameter0.5mm and Young’s modulus 2×1011N/m2 carries a load of mass M. The length of the wire with the load is 1.0m. A vernier scale with 10 divisions is attached to the end of this wire. Next to the steel wire is a reference wire to which a main scale, of least count 1.0mm , is attached. The 10 divisions of the vernier scale correspond to 9 divisions of the main scale. Initially, the zero of vernier scale coincides with the zero of main scale. If the load on the steel wire is increased by 1.2kg , the vernier scale division which coincides with a main scale division is ___. Take g=10

m

s2

and π=3.2