Chapter 12, Problem 71PQ

Three forces are exerted on the disk shown in Figure P12.71, and their magnitudes are F₃ = 2F₂ = 2F₁. The disk’s outer rim has radius R, and the inner rim has radius R/2. As shown in the figure, ${\stackrel{\to }{F}}_1$ and ${\stackrel{\to }{F}}_3$ are tangent to the outer rim of the disk, and ${\stackrel{\to }{F}}_2$ is tangent to the inner rim. ${\stackrel{\to }{F}}_3$ is parallel to the x axis, ${\stackrel{\to }{F}}_2$ is parallel to the y axis, and ${\stackrel{\to }{F}}_1$ makes a 45° angle with the negative x axis. Find expressions for the magnitude of each torque exerted around the center of the disk in terms of R and F₁.

FIGURE P12.71 Problems 71-75