Stress analysis of physical mechanics It depends on the situation and the given conditions. But I still don't quite understand. Now it's OK for me to solve it, but the old drawing of force analysis is not good. For example, I analyze the moving pulley with object a, resulting in the gravity of moving pulley g = 1000N, 100kg. It's heavier than me. What can I do!
In the force analysis, we should first clear the research object, and then isolate other objects for separate analysis, can not be together, if the research object is composed of several objects as a whole, that is, the research as a whole, we should isolate other objects, in the research. Hope to help you!
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