圖1所示傳送帶上有一個(gè)物體M,質(zhì)量為2kg ,它與傳送帶一起以lm/s的速度在水平方向向右勻速運(yùn)動(dòng),不計(jì)空氣阻力.請(qǐng)?jiān)趫D1中畫(huà)出M受力的示意圖.
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