Practicing Success

Target Exam

CUET

Subject

General Test

Chapter

Quantitative Reasoning

Topic

Trigonometry

Question:

A tree of height h m is broken by a storm in such a way that its top touches the ground at a distance of d m from its root. Find the height at which it is broken.

Options:

\(\frac{2h}{h^2 + d^2}\)

\(\frac{2h}{h^2 - d^2}\)

\(\frac{h^2 - d^2}{2h}\)

h² - d² + 2hd

Correct Answer:

\(\frac{h^2 - d^2}{2h}\)

Explanation:

let, AB = unbroken height of tree = h

C is the point of break

let, BC = x

using Pythagoras theorem;

(A'C)2 = (BC)2 + (A'C)2

(h - x)2 = d2 + x2

⇒ h2 - 2 hx + x2 = d2 + x2

⇒  2 hx = h2 - d2

x = \(\frac{h^2 - d^2}{2h}\)