Physics - Center of Mass Question with Solution | TestHub

Kinetic friction drags the block forward:$W_f>0$ on the block - (A) true. Plank speed is constant, so$\Delta K=0$ : net work on plank is zero - (B) true. Block reaches V in$t=\frac{V}{\mu g}$; plank moves$\frac{V^2}{\mu g}$, external work$=\mu Mg\cdot \frac{V^2}{\mu g}=M{V}^2$ - (C) true. Heat$=\mu Mg\times$ slip$=\mu Mg\left(\frac{V^2}{\mu g}-\frac{V^2}{2\mu g}\right)=\frac{1}{2}M{V}^2$ - (D) true. Answer: (A), (B), (C), (D)