91Ó°ÊÓ

$$\begin{gathered} L=4.5\text{m} \\ d=1.5\text{m} \\ W=580\text{N} \end{gathered}$$

Using the concept of static equilibrium, you can write the equation for the force and torque. From these equations, you can find forces and their directions. The equations are given below.

Static Equilibrium conditions:

$$\begin{gathered} ∑F_x=0 \\ ∑F_y=0 \\ ∑\mathrm{τ}=0 \end{gathered}$$

FBD of the diving board:

Applying equilibrium conditions to FBD:

$$\begin{gathered} ∑F_y=0 \\ {F}_1+F_2-W=0·······\left(1\right) \end{gathered}$$

Taking torque at point

$$\begin{gathered} ∑\mathrm{τ}=0 \\ {F}_1×d+W×\left(L-d\right)=0······\left(2\right) \\ {F}_1×1.5+580\left(4.5-1.5\right)=0 \end{gathered}$$

By solving for F₁ :

$F_1=-1160\text{N}$

By rounding off to appropriate significant figures:

$F_1=1200\text{N}$

The magnitude of force from the left pedestal is,

.$$\begin{gathered} F_1=1200\text{N} \\ =1.2×{10}^3\text{N} \end{gathered}$$

The negative value of F₁ indicates that it is directed downward.

Now plugging in the value of F₁ into equation no. :

$-1200+F_2-580=0$

By solving for F₂ :

$F_2=1780\text{N}$

By rounding off to appropriate significant figures:

$F_2=1700\text{N}$

The magnitude of force from the right pedestal is $F_2=1.7×{10}^3\text{N}$.

The positive value of F₂ indicates that it is directed upward.

The force on the left pedestal is in an upward direction, so the left pedestal is being stretched.

The force on right pedestal is in a downward direction, so the right pedestal is being compressed.