A steel wire of length 3.0cm is stretched through 2mm. If the cross-sectional area of the wire is 5.0mm², and the Young modulus of steel is 2.0x10''Nm?
Calculate the strain in the wire, the stress in the wire, and the energy density.

(a) assume the equation x = at^3 + bt describes the motion of a particular object, with x having the dimension of length and t having the dimension of time. determine the dimensions of the constants a and b. (use the following as necessary: l and t, where l is the unit of length and t is the unit of time.) (b) determine the dimensions of the derivative dx/dt = 3at^2 + b. (use the following as necessary: l and t, where l is the unit of length and t is the unit of time.)