A wire elongates by l mm when a load W is hanged from it. If the wire goes over a pulley and two weights W each are hung at the two ends, the elongation of the wire will be (in mm)

Elongation is the increase in length of a material when subjected to tensile stress. It is a measure of how much a material stretches under load and is typically expressed as a percentage of the original length. Elongation is crucial in assessing the ductility and strength of materials in engineering applications.

Class 11 Physics Chapter 8 investigates mechanical properties of solids focusing on stress strain and elasticity. It describes how solids respond to external forces and the resulting deformations. Key concepts include Hooke’s law types of stress and strain and the relevance of elasticity in engineering design applications and material selection for various structures.