JEE Mains · Physics · STD 11 - Fluid mechanics
- JEE Mains 2019
- Hard
- MCQ
A cubical block of side \(0.5\,m\) floats on water with \(30\%\) of its volume under water. ....... \(kg\) is the maximum weight that can be put on the block without fully submerging it under water ? [Take density of water \(= 10^3\,kg/m^3\) ]
Pick an option to check your answer.
Answer & Solution
Correct Answer
(D) \(87.5\)
Step-by-step Solution
Detailed explanation
\(0.3\,{\ell ^3}\,{\rho _\omega } = {\ell ^3}\rho \)
\(\rho = 300\frac{{kg}}{{{m^3}}}\)
\(m + {\ell ^3}\rho = {\ell ^3}{\rho _\omega }\)
\(M = {\ell ^3}\left( {{\rho _w} - \rho } \right) = {\left( 0.5 \right)^3}\left\{ {1000 - 300} \right\}\)
\( = 700 \times {\left( 0.5 \right)^3}\)
\( = 87.5\,kg\)
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