The shadow of a vertical tower AB on level ground is increased by 10 m, when the altitude of the sun changes from 45° to 30°, as shown in the figure. Find the height of the tower and give your answer correct to of a metre.

Question

KnowledgeBoat · Accepted Answer

Given, The height of the tower AB = h metres and the length of its shadow = x metres when the sun's altitude is 45°. When the sun's altitude is 30°, then the length of shadow of tower is 10 m longer, i.e., BA = h meters, AD = x meters and CD = 10 metres. From right angled △ABD, we get From right angled △BCA, we get Hence, the height of the tower is 13.7 m.

Mathematics

The shadow of a vertical tower AB on level ground is increased by 10 m, when the altitude of the sun changes from 45° to 30°, as shown in the figure. Find the height of the tower and give your answer correct to of a metre.

Heights & Distances

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