试题与答案

质量为m的物体在竖直向上的恒力F作用下以减速上升了H,在这个过程中,下列说法中正

题型:选择题

题目:

质量为m的物体在竖直向上的恒力F作用下以减速上升了H,在这个过程中,下列说法中正确的有         ( )

A.物体的重力势能增加了mgH

B.物体的动能减少了FH

C.物体的机械能增加了FH

D.物体重力势能的增加小于动能的减少

答案:

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