Question

An object is floating in a liquid, kept in a container. The container is placed in a lift. Choose the correct option.

• A. Buoyant force increases as the lift accelerates up
• B. Buoyant force decreases as the lift accelerates up
• C. Buoyant force remains constant as the lift accelerates
• D. The fraction of solid submerged into liquid decreases

Answer 1

Answer: (A)

As pressure gradient changes $\frac{dP}{dy}=\rho \left(g+a,\right)$
Buoyant force also changes, as it is due to pressure difference. But as body also accelerates with lift, so the fraction of volume submerged does not change and the extra buoyant force will provide the resultant force ${}^{\prime }m{a}^{\prime }$ to the body.