PHYSICS · Single correct · AP · Physics 1: Algebra-based · Force and Translational Dynamics · Force and Translational Dynamics
Problem
Two identical ideal springs, each with spring constant k, are attached to a block that can move without friction along a horizontal track.
• In Case I the springs are arranged in series between two fixed walls with the block in the middle.
• In Case II the springs are arranged in parallel, side by side, with one end of each spring fixed to a wall and the other ends attached to the block.
The block is pulled a distance Δx from equilibrium and held momentarily at rest. Which statement about the total elastic potential energy stored in the springs at that instant is correct?
(a) The series configuration stores half as much elastic potential energy as the parallel configuration.
(b) Both configurations store the same total elastic potential energy.
(c) The series configuration stores one-quarter as much elastic potential energy as the parallel configuration.
(d) The series configuration stores four times as much elastic potential energy as the parallel configuration.