An important and exam oriented question from trigonometry (height and distance) in which we to find the time consumed by the car to reach the foot of a tower if a straight highway leads to the foot of the tower, a man standing at the top of the tower observes a car at an angle of depression of 30∘ which is approaching the foot of the tower with uniform speed. Six seconds later, the angle of depression of the car is found to be 60∘.
Book RS Aggarwal, Class 10, Chapter 14, question no 14
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