# Problem 1-1|Stress | Mechanics of Materials| Ninth Edition| R.C. Hibbeler|

#### The shaft is supported by a smooth thrust bearing at B and a journal bearing at C. Determine the resultant internal loadings acting on the cross section at E.

SOLUTION:

The free-body diagram is shown below.

Solve for Cy by taking moment at point B

$\sum M_B=0$

$C_y\left(8\right)+400\left(4\right)-800\left(12\right)=0$

Pass a cutting plane at section E. The free-body diagram of the resulting figure is shown

Take the sum of forces in the x-direction, and equate to zero

$\sum F_x=0$

$N_E=0$

Take the sum of forces in the y-direction and equate to zero

$\sum F_y=0$

$V_E+1000-800=0$

$V_E=-200\:lb$

Take the sum of moments at point E

$\sum M_E=0$

$1000\left(4\right)-800\left(8\right)-M_E=0$

$M_E=-2400\:lb\cdot ft$

The negative signs indicates that  $V_E\:and\:M_E$ act in the opposite sense to that shown on the free-body diagram.