JEE Physics · Hard

Fluid Mechanics: Buoyancy MCQ

Solve this quality-checked JEE multiple-choice question, then review the correct answer and explanation.

Timer-based practiceDetailed answer reviewMobile-friendly flow
BuoyancyHardQuestion 30920

Question

A body weighs 50 N in air and 30 N in water. Volume of body is (g = 10 m/s², ρ_water = 1000 kg/m³):
  1. A
    2×10⁻³ m³
    Correct
  2. B
    3×10⁻³ m³
  3. C
    5×10⁻³ m³
  4. D
    2×10⁻² m³

Correct answer

2×10⁻³ m³

Explanation

Buoyant force = 50 − 30 = 20 N. V = F_b/(ρ_water × g) = 20/(1000×10) = 2×10⁻³ m³.