試題詳解

25. A 5.0 g marble is fired vertically upward from a spring gun. The spring must be compressed 8.0 cm if the marble is to just reach a target 20 m above the marble’s position on the compressed spring. What is the spring constant of the spring?
(A) 1.6 N/cm
(B) 1.8 N/cm
(C) 2.5 N/cm
(D) 3.1 N/cm
(E) 6.2 N/cm