A straight highway leads to the foot of a 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 a uniform speed. Six seconds later, the angle of depression of the car is found to be 60°. Find the time taken by the car to reach the foot of the tower from this point.
The diagram is:
Let us assume that ∠ADB = 30°, ∠ACB = 60° and time taken to reach from D to C = 6 seconds.
Time taken to reach from C to B = ?
In Δ ABD
In Δ ABC;
Now, on comparing (i) and (ii),
Hence, the time taken to reach from C to B = 3 second
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