By symmetry

$C_V = B_V = 400 ~ \text{lb}$

$\Sigma M_A = 0$

$8B_H = 6B_V + 8(500)$

$8B_H = 6(400) + 8(500)$

$B_H = 800 ~ \text{lb}$

Moment at *B*

$M_B = 500(2) = 1000 ~ \text{lb}\cdot\text{ft}$

Axial Force at *B*

$P_a = 400 + B_V \cos \alpha + B_H \cos \theta$

$P_a = 400 + 400(4/5) + 800(3/5)$

$P_a = 1200 ~ \text{lb compression}$

Maximum Compressive Stress Will Occur at Point *B*

$\sigma_c = \dfrac{P_a}{bd} + \dfrac{6M_B}{bd^2}$

$\sigma_c = \dfrac{1200}{4(4)} + \dfrac{6(1000)(12)}{4(4^2)}$

$\sigma_c = 1200 ~ \text{psi}$ *answer*

**Axial, Shear, and Moment Diagrams**

Not actually necessary but just in case you need it.

$P_1 = 800 \cos \theta = 800(3/5) = 480 ~ \text{lb}$
$P_2 = 900 \sin \theta = 900(4/5) = 720 ~ \text{lb}$

$P_3 = 800 \cos \theta = 800(3/5) = 480 ~ \text{lb}$

$P_4 = 400 \sin \theta = 400(4/5) = 320 ~ \text{lb}$

$P_5 = 500 \sin \theta = 500(4/5) = 400 ~ \text{lb}$

$V_1 = 800 \sin \theta = 800(4/5) = 640 ~ \text{lb}$

$V_2 = 900 \cos \theta = 900(3/5) = 540 ~ \text{lb}$

$V_3 = 800 \sin \theta = 800(4/5) = 640 ~ \text{lb}$

$V_4 = 400 \cos \theta = 400(3/5) = 240 ~ \text{lb}$

$V_5 = 500 \cos \theta = 500(3/5) = 300 ~ \text{lb}$

## Comments

## a block weighting 1000N is

a block weighting 1000N is kept on a rough plane inclines at 40 digress to the horizontal the coefficient of friction between the block and the plane is 0.6.Determine the smallest force inclines at 15 digress to the plane required just to move the block up the plane.

## Let: P=force needed to move

Let: P=force needed to move up the block

Take summation of forces vertical

Fv=0;

N=1000cos40+Psin15 eq.1

Take summation of forces horizontal Fh=0;

Pcos15=F+100sin40 eq.2

note: F=uN

where F stands for friction force

u stands for coefficient of friction

N stands for normal force on plane

Subst. eq. 1 to the formula;

F=0.6[(1000cos40+Psin15] eq.3

Then subst. eq.3 to eq.2;

Pcos15=0.6(1000cos40+Psin15)+1000sin40

Solving for P;

P=1359.94 N answer

Hope this will help you..

## sir what software you are

sir what software you are using to draw the beam diagram with different support conditions like pin and dollar supports

## MS Visio

MS Visio for figures in this page.