Question

A body B is capable of remaining stationary inside a liquid at the position shown in Fig. 4.205 (a). If the whole system is gently placed on smooth inclined plane (Fig. 4.205 (b)) and is allowed to slide down, then $(0<\theta <{90}^0)$

• A. The body will move up (relative to liquid)
• B. The body will move down (relative to liquid)
• C. The body will remain stationary (relative to liquid)
• D. The body will move up for some inclination $\theta$ and will move down for another inclination $\theta$

Answer 1

The correct option is B The body will move down (relative to liquid)

For body on horizontal surface,

$mg=F_b$

But for body on inclined surface

$mg\sin \theta =F_b^{\prime }$

$⟹F_b^{\prime }<F_b$

Since buoyancy force when on inclined plane is less than buoyancy force when on horizontal surface, the body will move down.