如图3-5-9所示,物体重G=100 N,并保持静止.绳AC与BC分别与竖直方向

如图3-5-9所示,物体重G=100 N,并保持静止.绳AC与BC分别与竖直方向成30°角和60°角,则绳AC的拉力为________N,绳BC的拉力为_________N.

图3-5-9

答案

解析:把重力分解,利用直角三角形知识可得FAC=mgsin60°=100× N=50 N≈86.6 N

    FBC=mgsin30°=100× N=50 N.

答案:86.6        50


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