问题
问答题
水平转台离转轴0.2m处放一质量为1.0g的木块，转台以ω＝2 /s匀速转动。求它转半周时间内摩擦力的冲量大小。
答案
0.8kgm/s
I=Δp=mv-（- mv）=2 mv=2 mωr=0.8kgm/s。
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水平转台离转轴0.2m处放一质量为1.0g的木块，转台以ω＝2 /s匀速转动。求它转半周时间内摩擦力的冲量大小。
0.8kgm/s
I=Δp=mv-（- mv）=2 mv=2 mωr=0.8kgm/s。
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