Assertion (A): When ice floats in water, its approximately 1/10th volume remains outside the water. Reason (R): The density of ice is approximately 10% less than the density of water. MCQ with Answer and Explanation

Assertion (A): When ice floats in water, its approximately 1/10th volume remains outside the water. Reason (R): The density of ice is approximately 10% less than the density of water.
A. Both A and R are true but R is NOT the correct explanation of A.
B. A is true but R is false.
C. Both A and R are true and R is the correct explanation of A.
D. A is false but R is true.
Answer: Option C
Solution (By JKSSB Mock Tests)
The density of ice is about 900 kg/m³ (0.9 g/cm³), while pure water is 1000 kg/m³ (1.0 g/cm³). According to the principle of floatation, the fraction of volume submerged is the ratio of densities: ρ_ice / ρ_water = 0.9. This means 90% is submerged, leaving exactly 10% (1/10th) exposed above the surface. Reason R explains Assertion A.

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