a block with mass m1=4.0kg is placed on top of a block with mass m2=12.0kg.(adsbygoogle = window.adsbygoogle || []).push({});

(a) if the acceleration of the lower block is a2=5.2m/s^2, calculate the minimum coefficient of static friction (u minimum, where u is mew), for the contact surface between 1 and 2, that will prevent block 1 from slipping with respect to block 2.

(b) the contact surfaces are polished and it is found that block 1 now slides on block 2. if the coefficient of kinetic friction uk=1/2u(minimum), u(minimum) found in a, what is the acceleration of block 1 with respect to the table (a1).

(c) what is the acceleration of block 1 with respect to the acceleration of block 2?

(d) what force must be applied to block 2 in (a) and (b) if the table is frictionless

im stuck on a, i dont know what to do with the acceleration, i thought about multiplying it with one of the masses, but i dont know which one

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# Homework Help: Friction problem (mass on top of another mass)

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