The pulling force is weight B
the retarding force is friction, and the component of weightA down the plane.
weightA down plane= mgCosTheta
Fricion= mu*mg*SinTheta.
Does that help? Remember, both masses are moving, so in F=ma, m is both masses.
Body A on an inclined plane weighs 102 N, and body B attatched to Body A by a rope and a frictionless, massless pulley weighs 35 N. The coefficients of friction between A and the incline are Us= .56 and Uk= .25 . Angle is 40°. Let the positive direction of an x axis be up the incline. In unit-vector notation, what is the acceleration of A if A is initially (a) at rest, (b) moving up the incline, and (c) moving down the incline?
1 answer