Question

A block of wood is floating on water with its dimensions $50cm\times 50cm\times 50cm$ inside water. The buoyant force acting on the block is X N. Find X. Take $g=9.8Nk{g}^{-1}$.

• A. $1225$
• B. $0.1225$
• C. $121.5$
• D. $1221$

Answer 1

Answer: (A)

$1225$

Density of water, $\rho =1000kg{m}^{-3}$
According to Archimedes principle, the buoyant force acting on an object is equal to the weight of the liquid displaced.
Volume of water displaced = $50\times 50\times 50\times {10}^{-6}{m}^3=0.125m^3$
Weight of water displaced = $0.125\times 1000\times 9.8=1225N$
$X=1225$