Beam Deflection
A standard 2x4 can actually be used to measure the weight of a person. Finding the moment of inertia and the elasticity of the 2x4 beam will help with this task. First, you must find the moment of inertia of the beam. You will use the equation lxx=bh^3/12 to find the moment of inertia for when the beam is in the vertical position and the horizontal position. You will need to measure the distance from the floor to the bottom of the beam before and after the force of your volunteered person is applied to the 2x4. You will then calculate the maximum beam deflection by subtraction the applied loading distance from the pre-loading distance. To find the beam's Modulus of Elasticity, use the equation DeltaMax= Fl^3/48El. This equation can be manipulated to find the variable E as long as all of the other variables are already solved for. The manipulated equation for E will look like E=Fl^3/48lxxDeltaMax. Knowing the moment of inertia can help engineers make structures cheaper and lighter and help improve our society.