Right, so the **Young's modulus** of a material is a measure of it's rigidity. The higher the value of the Young's modulus, the more rigid the material is.Ok, so the Young's modulus, E, is equal to the **stress **that the material experiences divided by the **strain **experienced by the material.The **stress, σ**, of a material is equal to the force, F, applied to this material, divided by the area, A, upon which this force is applied. The equation for this is:**σ = F/A**On the other hand, the **strain, ε**, of the material is equal to the **extension **of the material, **e** (how much the material has extended by having this force applied to it), divided by the original **length, l**, of the material. The equation for strain is**ε = e/l**The Young's modulus is equal to the stress divided by the strain, so:**E= σ/ε = (F/A)/(e/l) = (F L)/(Ae)So, E = (Fl)/(Ae)**For example, If a metal wire of original length 2cm