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प्रश्न
In the below given figure, a tower AB is 20 m high and BC, its shadow on the ground, is 20√3 m long. Find the sun’s altitude.
उत्तर
LetAB be the tower and BC be its shadow.
AB = 20, BC = 20√3
In ΔABC,
`tan theta= `
`tan theta=20/(20sqrt3)`
`tan theta=1/sqrt3`
`but,tan30=1/sqrt3`
`theta=30^@`
The Sun is at an altitude of 30º .
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