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प्रश्न
Find the length of the shadow cast by a tree 60 m high when the sun's altitude is `30^circ`.
उत्तर
Let AB be the tree of height 60 m and BC be its shadow .
In ΔABC
`"AB"/"BC"` = `tan30^circ`
`60/"BC" = 1/sqrt(3)`
`"BC" = 60sqrt(3)` m
So , height of tower is `60sqrt(3)` m .
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