1) A 12-kg block on a horizontal frictionless surface is attached to a light spring (force constant =0.80 kN/m). The block is initially at rest at its equilibrium position when a force (magnitude P= 80 N) acting parallel to the surface is applied to the block, as shown. What is the speed of the block when it is 13 cm from its equilibrium position?
a) Write the correct energy equation, i.e. in the form of how changes in energy relate to each other.
b) Calculate the speed requested above.