A 1.50 kg block is at rest on a table and is attached to a horizontal spring with a spring constant of 19.6 N/m. The spring is initially not stretched. A constant force of 20 N horizontal force is applied to the object causing the spring to stretch. Determine the speed of the block when it has stretched 0.300 m. Assume the table is frictionless. The way I did it: E = (mv^2)/2 + (kx^2)/2 1/2kA^2 = (mv^2)/2 + (kx^2)/2 Do I simply rearrange for speed?