从物理学角度看,图所示的情景说明______________________________________.

从物理学角度看,图所示的情景说明______________________________________.

答案

做功可以改变物体的内能(或摩擦可以生热) 

【解析】图中情景天气很冷,老人采用搓手的方式取暖,是利用了摩擦可以生热,即做功来改变物体内能的

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