A disc of mass m and radius R lies on a plank of the same mass m. Friction is sufficient to prevent slipping between disc and plank. A horizontal force F is applied at the center of the disc.

Question

G1 Physics · Accepted Answer

Let friction magnitude be f. For the disc, F-f=m × acceleration of disc and fR=(½mR²)α; for the plank, f=m × acceleration of plank. No slip between disc and plank gives acceleration of disc-acceleration of plank=αR. Solve these three equations.