Hesi A2 Exam Review Questions And Answers

A level Physics Paper 2Get a hintHooke's Law>>> ∆F = k∆x where k is the stiffness of the objectStress>>> σ=F/A where F is force and A is cross sectional areaStrain>>> ε=∆x/x where x is the original length of the material and ∆x is the extensionYoung Modulus>>> Stress/StrainTensile stress/strain>>> Causes the length of the material to increase, the forces act away from the centerCompressive stress/strain>>> Causes the length of the material to decrease, the forces act towards the centerForce Extension graph>>> Stress strain graph>>> Stress Strain Graphs for Different Materials>>> Stiffer materials have a steeper gradient.Stronger materials have a large breaking stressBrittle materials have a very small plastic regionsStress Strain Graph for Rubber>>> Limit of Proportionality>>> *The point until which force and extension (or stress and strain) are directly proportional. After this point it may behave elastically, but they will no longer be proportional*Elastic Limit>>> *The point beyond which the material is permanently deformed, it won't return to it's original shape*Yield Point>>> *Beyond this point the material suddenly undergoes a large increase in extension (it 'gives') as the atomic substructure is rearranged*Breaking stress>>> *The value of stress in a material when it breaks*Elastic