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Question
There are two poles having heights 8 m and 4 m on plane ground as shown in fig. Because of sunlight shadows of smaller pole is 6m long, then find the length of shadow of longer pole.
Solution
Here, AC and PR represent the bigger and smaller poles, and BC and QR represent their shadows respectively.
Now,
ΔACB ∼ ΔPRQ .....[Vertical poles and their shadows form similar figures]
∴ `"CB"/"RQ" = "AC"/"PR"` ......[Corresponding sides of similar triangles]
∴ `x/6 = 8/4`
∴ x = `(8 xx 6)/4`
∴ x = 12 m
∴ The shadow of the bigger pole will be 12 metres long at that time.
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