Question

    A block rests on another block, and the lower one is

    pulled with a horizontal force. If the coefficient of friction between them is μ, what is the maximum acceleration of the system so that the upper block does not slide?
    A μg Correct Answer Incorrect Answer
    B g/μ Correct Answer Incorrect Answer
    C μmg Correct Answer Incorrect Answer
    D mg Correct Answer Incorrect Answer

    Solution

    To ensure that the upper block does not slide on the lower one, the frictional force between them must be able to provide the necessary acceleration to the upper block. Let:

    • μ = coefficient of friction between blocks
    • g = acceleration due to gravity
    • a = acceleration of the system (both blocks moving together)
    For the upper block not to slide, maximum friction should be able to provide the required acceleration:

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