Question

If a 30 m ladder is placed against a 15 m wall such that it just reaches the top of the wall, then the elevation of the wall is equal to:

• A. 45°
• B. 30°
• C. 60°
• D. 50°

Hint:

In a right triangle, use trigonometric ratios like \(\tan \theta = \frac{\text{opposite}}{\text{adjacent}}\) to find the angle of elevation.

Answer 1

The Correct Option is A

In this scenario, we have a right-angled triangle with the ladder as the hypotenuse, the wall as the vertical side, and the ground as the horizontal side. The angle of elevation is given by the formula: \[ \theta = \tan^{-1} \left(\frac{\text{opposite}}{\text{adjacent}}\right) = \tan^{-1} \left(\frac{15}{30}\right) = 45° \]
Therefore, the correct answer is "45°."