19. Fluid Mechanics

Fill in the blank: An object is most likely to sink in water if its average density $>$ the density of water.

For an object to float in water, what must be true about its weight compared to the weight of the water it displaces?$\mathrm{W\_\{object\}}$ and $\mathrm{W\_\{water\}}$?

A person could float most easily in water that has which characteristic?

In the context of buoyancy, does the volume of an object alone determine whether it will float or sink in a fluid?

If the buoyant force exerted by water on a stick ($F$_b) is less than the weight of the stick ($W$), what will happen to the stick when it is placed in water?

A homogeneous rectangular gate is $4$ ft wide and $8$ ft long, and it weighs $800$ lb. The gate is hinged along its top edge and is submerged vertically in water so that its top edge is at the water surface. What is the minimum depth of water above the bottom edge of the gate required for the hydrostatic force to just begin to open the gate?

Why is it easier to float in saltwater than in freshwater?

Which statement best explains the reason some insects can walk across the surface of a lake?

A helium balloon of volume $V$ is fully submerged in air of density ${\rho }_{\mathrm{air}}$ under standard atmospheric pressure. What is the magnitude of the buoyant force $F_b$ acting on the balloon?

Which of the following determines an object's ability to float in water?

Will the same ship float higher in $\mathrm{salt} \mathrm{water}$ than in $\mathrm{freshwater}$? Choose the best explanation.

According to Archimedes' principle, if the buoyancy of an object is positive, it will: $F\_b>0$

Why does a small pebble sink in water?

When an object is completely submerged in water, how does its $V\_\mathrm{object}$ compare to the $V\_\mathrm{displaced}$ of water?

When a piece of ice floats in water, what fraction of its volume remains above the water surface?