Young S Modulus Experimental Determination — the NEET Physics formula with its derivation, variables, validity constraints and worked solver.
Young's Modulus (Experimental Determination) Applies to the elastic deformation of solid wires under tensile stress within the proportionality limit, typically used in Searle's apparatus experiments. Define Longitudinal Stress = Force / Area = (M g) / (pi r 2). Define Longitudinal Strain = Change in Length / Original Length = l / L. Young's Modulus (Y) = Stress / Strain. Substitute expressions for stress and strain to obtain Y = (M g L) / (pi r 2 l). The wire must be within its elastic limit. The cross-section of the wire is assumed to be perfectly circular. The mass of the wire itself is neglected. Temperature must remain constant to avoid thermal expansion errors. Thinking Young's Modulus depends on the dimensions (L, r) of the wire; it is a material-specific constant. Confusing 'l' (extension) with the total final length of the wire. Forgetting to square the radius in the denominator.