【題目】關(guān)于公式W＝Ek2－Ek1＝ΔEk，下述正確的是（ ）

A．功就是動(dòng)能，動(dòng)能就是功

B．功可以變?yōu)槟埽芸梢宰優(yōu)楣?/span>

C．動(dòng)能變化的多少可以用功來量度

D．功是物體能量的量度

【答案】C

【解析】功和能（動(dòng)能）是兩個(gè)不同的概念，也不可以相互轉(zhuǎn)化，動(dòng)能定理只是反映了合外力做的功與物體動(dòng)能變化的關(guān)系，即反映了動(dòng)能變化多少可以由合外力做的功來量度．

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