WBJEE 2025 Physics and Chemistry Papers

One end of a stecl wire is fixed to the ceiling of an elevator moving up with an acceleration 2m∕ s2 and a load of 10 kg hangs from the other end. If the cross section of the wire is 2cm2, then the longitudinal strain in the wire will be ( g=10m∕ s2 and Y=2.0×1011N∕m2 )