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匀变速直线运动

> 如图，水平传送带A、B两端相距S=2m，工件与传送带间的动摩擦因数μ=0.4。工件滑上A端瞬时速度V A=5m／s，达到B端的瞬时速度设为V B，则 A．若传送带不动，则V B=3m／s B．若传送带逆时针匀速转动，则V B<3m／s C．若传送带以某一速度顺时针匀速转动，则一定V B>3m／s D．若传送带以2m／s顺时针匀速转动，则V B=2m／s

问题：

发布时间：2024-09-12

如图，水平传送带A、B两端相距S=2m，工件与传送带间的动摩擦因数μ=0.4。工件滑上A端瞬时速度V _A=5m／s，达到B端的瞬时速度设为V _B，则

A．若传送带不动，则V _B=3m／s
B．若传送带逆时针匀速转动，则V _B<3m／s
C．若传送带以某一速度顺时针匀速转动，则一定V _B>3m／s
D．若传送带以2m／s顺时针匀速转动，则V _B=2m／s

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