Problem $1$: Solve Problem $3-69.$ Assume the tensions on pulley A are $2000$ and $3-68*$ to A countershaft carrying two V$-$belt pulleys is shown in the figure. Pulley A receives power from

$3-71*$ a motor through a belt with the belt tensions shown. The power is transmitted through the shaft

and delivered to the belt on pulley $B.$ Assume the belt tension on the loose side at $B$ is $15$ per$-$

cent of the tension on the tight side.

$($a$)$ Determine the tensions in the belt on pulley $B,$ assuming the shaft is running at a constant

speed.

$($b$)$ Find the magnitudes of the bearing reaction forces, assuming the bearings act as simple

supports.

$($c$)$ Draw shear$-$force and bending$-$moment diagrams for the shaft. If needed, make one set for

the horizontal plane and another set for the vertical plane.

$($d$)$ At the point of maximum bending moment, determine the bending stress and the torsional

shear stress.

$($e$)$ At the point of maximum bending moment, determine the principal stresses and the max$-$

imum shear stress.

$470$ N $,$ respectively.