問題詳情
19．右图为两分子系统的势能与两分子间距离的关系曲线。
下列说法正确的是
(A)．当大于r1时，分子间的作用力表现为引力
(B)．当小于r1时，分子间的作用力表现为斥力
(C)．当等于r2时，分子间的作用力为零
(D)．当由r1变到r2的过程中，分子间的作用力做负功
參考答案
答案：B,C
難度：適中0.5
統計：A(0),B(0),C(0),D(0),E(0)
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