Solids - created from Mind Map

Density Density= m/v ρ Mass per unit volume

Springs Hooke's Law Extension applied is directly proportional to the load applied Some materials do not obey, eg. rubber Providing the limit of proportionality is not exceeded! ΔL ∝ F F=KΔL K= Spring constant in n/m

Young's Modulus Tensile Stress Tensile Strain Ratio of tensile stress applied to tensile strain produced Pa or N/m^2 E or Y Stress- Strain graph The perpendicular force applied per unit cross-sectional area Tensile Stress = F/A Pa or N/m^2 Extension produced per unit original length No units ΔL/L Gradient = E Area underneath = Strain energy per unit volume

Force-Extension Graphs F= EA/L ΔL Energy Stored EA/l = gradient E = gradient * l / A Work Done = Force x Distance 1/2 F ΔL FΔs = Area under graph Energy Stored = Work Done = 1/2 b x h = 1/2 ΔL x F = 1/2 F ΔL

Key Terms Limit of proportionality- The point beyond which Hooke's law is no longer obeyed Elastic behaviour- Original size & shape is regained after force is removed Plastic Behaviour- Some permanent deformation when force is removed Elastic Limit - The maximum amount of stretch whilst still regaining original size and shape when force removed Yield Point- The point at which the material 'gives' a little. There is a marked increase in extension due to crystal planes sliding across eachother Ultimate Tensile Strength - The maximum tensile stress that can be applied to a material without it breaking Stiff - Very little deformation when a force is applied Brittle - Very stiff and breaks with hardly any plastic deformation Fracture - Cracks appear on the surface of the solid when a force is applied causing it to break Ductile - Shows plastic deformation

Solids