Difficulty: Easy
Correct Answer: 60 °
Explanation:
Introduction / Context:Angle of elevation θ relates height h and shadow s by tan θ = h/s. If s is a fixed fraction of h, tan θ is a fixed constant leading to a standard angle result.
Given Data / Assumptions:
Concept / Approach:Compute tan θ = h/s = h / (h/√3) = √3, then identify θ from the exact trig value.
Step-by-Step Solution:tan θ = √3 ⇒ θ = 60°
Verification / Alternative check:At 60°, tan = √3; plugging back yields s = h/√3 as stated. The geometry is consistent.
Why Other Options Are Wrong:30° gives tan = 1/√3; 45° gives tan = 1; 90° is vertical and produces no finite shadow; 15° is much smaller.
Common Pitfalls:Using cot instead of tan or misreading “1 √3 times” as √3 times. Here it is explicitly 1/√3 of the height.
Final Answer:60 °
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