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一質(zhì)點(diǎn)在鉛垂平面內(nèi)作圓周運(yùn)動(dòng),當(dāng)質(zhì)點(diǎn)恰好轉(zhuǎn)過一周時(shí),其重力的功為零,對(duì)嗎?為什么?

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正確答案:

對(duì)的。因?yàn)橹亓Φ墓Φ扔谫|(zhì)點(diǎn)的質(zhì)量與其始末位置的高度差的乘積,當(dāng)高度差為零時(shí),重力的功為零。

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試題分類: 大學(xué)英語四級(jí)
練習(xí)次數(shù):2次
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試題分類: 大學(xué)英語六級(jí)
練習(xí)次數(shù):2次
試題分類: 資料員
練習(xí)次數(shù):0次
試題分類: 安全員
練習(xí)次數(shù):1次
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練習(xí)次數(shù):0次
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