A man standing on the line joining the two poles finds that the top of the poles make anĀ angle of elevation of $$60^\circ$$ and $$45^\circ$$ respectively. After walking for sometime towards the otherĀ pole, the angles change to $$30^\circ$$ and $$60^\circ$$ respectively. The ratio of the height of the poles is :
Let 'a' and 'b' be the heights of the two poles
X be the initial position of the man and the angles of elevation be $$60^0$$ and $$45^0$$
Distance between pole 1 and XĀ =Ā $$\ \frac{\ a}{\sqrt{\ 3}}$$ and distance between pole 2 and X = b
Let Y be the position of the man after walking sometime towards the other pole =Ā
Distance between Y and pole 1 =Ā $$\ \ a\sqrt{\ 3}$$ and distance between the pole 2 and Y =Ā $$\ \frac{\ b}{\sqrt{\ 3}}$$
Since the distance between the poles will remain the sameĀ
$$\ \frac{\ a}{\sqrt{\ 3}}$$ + b =Ā $$\ \ a\sqrt{\ 3}$$ +Ā $$\ \frac{\ b}{\sqrt{\ 3}}$$
$$\ \frac{\ a}{b}=\ \ \frac{\ \sqrt{\ 3}-1}{2}$$
A is the correct answer.
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