A straight tree breaks due to storm and the broken part bends so that the top of the tree touches the ground making an angle of 30° with the ground . The distance from the foot of the tree to the point , where the top touches the ground is 10 m. Find the total height of the tree?
(AB+BC) = $$h$$ is the whole height of the tree, the tree breaks down from point A, BC = 10 m
In $$\triangle$$ ABC,
=> $$tan(30^\circ)=\frac{AB}{BC}$$
=> $$\frac{1}{\sqrt{3}}=\frac{AB}{10}$$
=> $$AB=\frac{10}{\sqrt{3}}$$ m ---------(i)
Again, in $$\triangle$$ ABC,
=> $$cos(30^\circ)=\frac{BC}{AC}$$
=> $$\frac{\sqrt{3}}{2}=\frac{10}{AC}$$
=> $$AC=\frac{20}{\sqrt{3}}$$ m ----------(ii)
Adding equations (i) and (ii),
=> $$AB+AC=\frac{10}{\sqrt{3}}+\frac{20}{\sqrt{3}}$$
=> $$h=\frac{30}{\sqrt{3}}=10\sqrt{3}$$ m
=> Ans - (A)
Create a FREE account and get: