Question

Let the cylinder is prevented from moving up, by applying a force and water level is further decreased. Then, height of water level($h_2$ in figure) for which the cylinder remains in original position without application of force is

• A. $h/3$
• B. $4h/9$
• C. $2h/3$
• D. $h$

Answer 1

Answer: (B)

$4h/9$

Directly on balancing forces, we get

$[P_0+\rho gh\_1]\pi \left(4r^2\right)+\frac{\rho }{3}\pi 4r^{2}hg$
$=[P_0+\rho g(h\_1+h\_2\left)\right]\pi \left(3r^2\right)+P_0\pi r^{2}h$

On solving we get,

$h_2=4\frac{h}{9}$