Energy-Work: Conservation of mechanical energy Homework 4: A 20.0-kg block is connected to a 30.0-kg block by a string that passes over a frictionless pulley. The 30.0-kg block is connected to a spring that has negligible mass and a spring constant 250 N/m. The spring is un-stretched initially and the incline is frictionless. Find the maximum distance as the 20.0-kg block moving up. 20.0 kg 30.0 kg 40.0