试题与答案

如图所示,把一个质量为M的三角形物体放在粗糙的水平面上,三角形物体的斜面是光滑的

题型:计算题

题目:

如图所示,把一个质量为M的三角形物体放在粗糙的水平面上,三角形物体的斜面是光滑的,用一根轻绳OB吊一个质量为m的小球(可视为质点)放在斜面上,已知AO=AB。求

(1)当三角形物体静止时,绳OB对球的拉力多大?

(2)要求整个系统处于图示静止状态,物体与水平面间的摩擦因数不得小于多少?

(3)如果剪断绳子要求三角形物体保持静止状态,则物体与水平面间的摩擦因数又要求多大?(题中假设最大静摩擦力等于滑动摩擦力)

答案:

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