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The sliding blocks a and B with mass m and M 'respectively are stacked on a smooth horizontal table, as shown in the figure. The static friction factor between a and B is u'. The dynamic friction factor is u. The system was at rest. Now there is a horizontal force F acting on a, so that a and B do not slide relative to each other F
The moment of relative sliding is only related to the static friction coefficient u, but not to the dynamic friction coefficient
The stress of a and B is analyzed respectively
The horizontal force of a is f-mgu (with F direction as positive direction)
The horizontal force of B is MGU
When relative sliding occurs, the acceleration of a is greater than that of B
That is, (f-mgu skim) / M > MGU skim / M skim
So the condition of no relative sliding is (f-mgu) / m
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