Q29 of 47 Page 1

150 spherical marbles, each of diameter 1.4 cm, are dropped in a cylindrical vessel of diameter 7cm containing some water, which are completely immersed in water. Find the rise in the level of water in the vessel.

Volume of water displaced = Volume of spherical marbles * Number of marbles

⸫ Volume of water displaced = πr3× 150


=


= 11 × 0.2 × 1.4 × 1.4 × 50


= 215.6 cm3


Let the rise in the water level be h cm


⸫ πr2h = 215.6


⇒ = 215.6


⇒ h =


⸫ h = 5.6 cm


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