You stick two blocks together with Velcro. The manufacturer rated the Velcro as needing a force of 50N to separate the side you are using when applied to solid surfaces. You set up the connected blocks so that the top of one is attached to the end of a vertical spring. The blocks each have a mass m = 0.75kg, and the spring constant is k = 1200N/m. Find the maximum possible amplitude of oscillation at which the blocks will hold together.