Question

A rectangular block is $10cm\times 10cm\times 15cm$ in size is floating in water with $10cm$ side vertical. If floats with $15cm$ side vertical, then the level of water will

• A. Rise
• B. Fall
• C. Remain same
• D. Change according to density of block

Answer 1

The correct option is C. Remain same

For floating of a block, the buyout force balances its weight,

$F_b=mg$

$V_f{\rho }_{f}g=V_b{\rho }_{b}g$..................(i)

where, $V_f$ = volume of fluid displaced

$V_b$ = Volume of block

$V_b=1500c{m}^3$ remain the same always, no matter which side is in the vertical position while floating.

Hence, from Eq.(i) $V_f$ = constant

∴ The level of water will remain constant in the container as the volume of liquid displaced will be equal in both cases.