The shadow of a tower at a time t is 3 times longer than its shadow when the angle of elevation of the sun is 60 degrees. The angle of elevation at time t is

1. When sun is at 60 degrees, shadow = h/tan(60) = h/(square root of 3). 2. New shadow = 3 × h/(square root of 3) = h × square root of 3. 3. tan(new) = h / (h square root of 3) = 1/(square root of 3); so new = 30 degrees. _Source: syllabus Mathematics, Ch 9 "Some Applications of Trigonometry", §9.2_