试题与答案

关于动能和速度,下列说法正确的是() A.物体的速度发生变化,动能一定发生变化

题型:选择题

题目:

关于动能和速度,下列说法正确的是(   )

A.物体的速度发生变化,动能一定发生变化

B.物体的速度发生变化,动能可能不变

C.物体的动能不变,速度一定不变

D.物体的动能发生变化,速度可能不变

答案:

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A.therefore

B.consequently

C.however

D.moreover

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