Relating work and changes in energy

Three experiments are conducted with identical blocks on a level, frictionless surface, as shown below. Each block starts from rest and is pushed through a distance d0 by a hand that exerts a constant horizontal force of magnitude F0. l Emergent I I l Experimenl 2 l Btperiment 3 Each hand pushes ' ' Each hand pushes Each hand pushes l With a constanl force I = , with a constant force l with a constant fame Dflnngniludc Fa l 'l of magnitude F . " l I - r ofmagnitude Fa In experiment 1, the blocks are connected by an ideal massless spring that is initially neither stretched nor compressed. The spring has spring constant 161. At the end of the interval shown, each block has a speed of zero. In experiment 2, each block has a speed of of? at the end of the interval shown. In experiment 3, experiment 1 is repeated using an ideal massless spring of constant k3 , which is less than 161. However, at the end of experiment 3, each block is still moving and has a speed of 110. Systems 1 and 3 consists of the two blocks and the spring in experiments 1 and 3. System 2 consists of the two blocks in experiments 2. Create four rankings according to the following quantities, from largest to smallest. If any quantity is zero, state so explicitly. Briey explain each of your rankings. i. the absolute value of the network done by external forces ii. the absolute value of the change in total energy iii. the absolute value of the change in potential energy iv. the absolute value of the change in kinetic energy