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Statement-1: When a body floats with parts of it immersed in two immiscible liquids, the buoyant force contributed by liquid-1 has magnitude rho1*V1*g (V1 = volume immersed in liquid-1). Statement-2: The total buoyant force on the body equals rho1*V1*g + rho2*V2*g. Choose the correct option.
- Statement-1 is true, Statement-2 is true and Statement-2 is the correct explanation of Statement-1.
- Statement-1 is true, Statement-2 is true but Statement-2 is NOT the correct explanation of Statement-1.
- Statement-1 is true, Statement-2 is false.
- Statement-1 is false, Statement-2 is true.
Correct answer: Statement-1 is true, Statement-2 is true and Statement-2 is the correct explanation of Statement-1.
Solution
Each liquid exerts buoyancy equal to the weight of its own displaced volume: rho1*V1*g from liquid-1 and rho2*V2*g from liquid-2 (Statement-1 is true). The total upthrust is their sum, rho1*V1*g + rho2*V2*g (Statement-2 true). Since the total is built precisely by adding the individual contributions, Statement-2 correctly explains Statement-1.
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