Bennett Mechanical Test Fluid Mechanics and Hydraulics 4

Question 1

An object floats in water when its weight is:

Accepted Answer

Equal to the buoyant force

Answer

An object floats in equilibrium when its weight equals the buoyant force pushing up.

Question 2

Archimedes' principle states the buoyant force on a submerged object equals the weight of the:

Accepted Answer

Fluid displaced by the object

Answer

Buoyant force equals the weight of the fluid the object displaces.

Question 3

Why does a steel ship float even though steel is denser than water?

Accepted Answer

The hull shape displaces enough water to equal the ship's weight

Answer

The hollow hull displaces a large volume of water whose weight supports the ship.

Question 4

Two balls of equal size are submerged: one is solid steel, one is hollow plastic. The buoyant force on them is:

Accepted Answer

The same on both

Answer

Buoyant force depends on displaced volume, which is equal for same-size objects.

Question 5

An object will sink in a fluid if its average density is:

Accepted Answer

Greater than the fluid's density

Answer

When an object is denser than the fluid, gravity exceeds buoyancy and it sinks.

Bennett Mechanical Test Practice Test