At which of the following times does the spring exert its maximum force on the block? {Ans: 2 s}A block on a horizontal surface is attached to a horizontal spring of negligible mass and spring constant 30N/m. The other end of the spring is attached to a wall, and there is negligible friction between the block and the horizontal surface. The block-spring system experiences simple harmonic motion, as shown in the graph. What is the change in spring potential energy of the block-spring system from when the block is released to when the block has its greatest speed? {Ans: 240 J}The students must conduct an experiment to determine the magnitude of the force exerted on the block when the block is at a position of A2, where A is the amplitude of oscillation for the block-spring system. For each trial, the students attach blocks of different mass m to the spring, stretch the spring a known distance A, release the system from rest, measure the period of oscillation T, and then measure the maximum velocity v of the system. How should students use a graph to determine the magnitude of the force under consideration? {Ans: Determine the