A carpenter makes stools for electricians with a square top of side $ 0.5 \mathrm{~m} $ and at a height of $ 1.5 \mathrm{~m} $ above the ground. Also, each leg is inclined at an angle of $ 60^{\circ} $ to the ground. Find the length of each leg and also the lengths of two steps to be put at equal distances.
Given:
A carpenter makes stools for electricians with a square top of side \( 0.5 \mathrm{~m} \) and at a height of \( 1.5 \mathrm{~m} \) above the ground. Also, each leg is inclined at an angle of \( 60^{\circ} \) to the ground.
To do:
We have to find the length of each leg and also the lengths of two steps to be put at equal distances.
Solution:
Let $AC$ be the leg of the stool whose top is a square-shaped of side $AB$.
Height of the stool $AS = 1.5\ m$ and the angle of inclination of the leg of the stool is $60^{\circ}$.
Let $AC=x\ m$
In right $\Delta \mathrm{ACS}$,
$\sin \theta=\frac{\text { Perpendicular }}{\text { Hypotenuse }}$
$=\frac{\mathrm{AS}}{\mathrm{AC}}$
$\Rightarrow \sin 60^{\circ}=\frac{1.5}{x}$
$\Rightarrow \frac{\sqrt{3}}{2}=\frac{3}{2 x}$
$\Rightarrow 2\sqrt{3} x=3 \times 2$
$\Rightarrow x=\frac{6}{2 \sqrt{3}}$
$=\sqrt{3}$
$=1.732$
The length of the leg is $1.732 \mathrm{~m}$.
Given that there are two steps on equal distance.
This implies,
The distance between two steps $=\frac{1.5}{3}=0.5 \mathrm{~m}$
From the figure,
$\mathrm{EF}\|\mathrm{GH}\| \mathrm{CD}$
$\angle \mathrm{E}=\angle \mathrm{G}=\angle \mathrm{C}=60^{\circ}$ (Corresponding angles are equal)
In $\Delta \mathrm{AGT}$,
$\tan 60^{\circ}=\frac{\mathrm{AT}}{\mathrm{GT}}$
$\Rightarrow \sqrt{3}=\frac{1}{\mathrm{GT}}$
$\Rightarrow \mathrm{GT}=\frac{1}{\sqrt{3}}$
$=\frac{\sqrt{3}}{3}$
$=\frac{1.732}{3}$
$=0.577\ m$
$\mathrm{GH}=0.5+0.577+0.577=1.645 \mathrm{~m}$
Similarly,
In $\triangle \mathrm{AEU}$,
$\tan 60^{\circ}=\frac{\mathrm{AU}}{\mathrm{EU}}$
$\Rightarrow \sqrt{3}=\frac{0.5}{\mathrm{EU}}$
$\Rightarrow \mathrm{EU}=\frac{0.5}{\sqrt{3}}$
$=\frac{1}{2 \sqrt{3}}$
$=\frac{\sqrt{3}}{6}$
$=\frac{1.732}{6}$
$=0.288$
$\mathrm{EF}=0.5+0.2886+0.2886=1.077 \mathrm{~m}$
The length of each leg is $1.732\ m$ and the lengths of two steps to be put at equal distances are $1.1077\ m$ and $1.654\ m$.
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