試題詳解

17. Two blocks (with the same mass m) connected by a spring of negligible mass are at rest on a frictionless table, as shown in the upper part of figure. The separation distance of the blocks when the spring is relaxed is L. During a time interval △t, a constant force of magnitude F is applied horizontally to the left block, moving it through a distance x₁ as shown in the lower part of figure. During this time interval, the right block moves through a distance x₂. At the end of this time interval when the force is removed, what is the maximum energy could be momentarily stored in the spring?

(A) F(x₁+x₂)
(B) F(x₁+x₂)/2
(C) F(x₁-x₂)/2
(D) F(x₁-x₂)
(E) It cannot be determined.