Question
A cylindrical tank of 28 cm base radius is partly filled
with water. How many spherical iron balls of 1cm radius are added in it in order to increase the water level by 5cm?Solution
Base radius of a cylindrical tank = 28 cm Change in the rise of water in a cylindrical tank = Volume of a bullet Radius of a iron = 1 cm No. of bullets = (Change in the rise of water in a cylindrical tank )/(Volume of a bullet ) = (π r2h)/((4 )/(3 ) π r3) = (π × 28 × 28 × 5 )/(π (4 )/(3 ) × 13) = (28 × 28 × 5 × 3 )/(4 ) = 2,940 To increase the water level by 5cm we need 2,940 bullets.
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