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Question
A glass cylinder with a diameter 20 cm has water to a height of 9 cm. A metal cube of 8 cm edge is immersed in it completely. Calculate the height by which the water will up in the cylinder. Answer correct of the nearest mm. (Take π = 3.142)
Solution
Let the height by which the water ups be = h cm
Volume of the increase in water = 3.142 x 10 x 10 x h cm3
Volume of the cube = 8 x 8 x 8 cm3
Both the above volumes are equal
∴ 3.142 x 10 x 10 x h = 8 x 8 x 8
h = `(8 xx 8 xx 8)/(3.142 xx 10 xx 10) = 1.6` cm
The height h = 16 mm.
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