Buoyancy

Suppose a cubic foot of steel (weight: 480 lb) is below the surface of water.

What is the buoyant force exerted on it by the water?

Suppose a cubic foot of steel (weight: 480 lb) is below the surface of water.

What will be the apparent approximate weight of the steel?

A cubic foot of pine wood weighs about 30 pounds.  If it were pushed underwater, the byoyant force on it would also be 62.4 lb.  But since the byoyant force is greater than its weight, pine will not stay underwater unless held there.

Calculate how much of its volume will remain under water when it floats.

1. What weight of water will the 30-lb piece of wood have to displace in order to float? 1($) lb
2. What is the volume of this weight of water? 2($) ft³
3. How much of the wood will be below water level as the block of wood floats? 3($) ft³

A cubic foot of pine wood weighs about 30 pounds.  If it were pushed underwater, the byoyant force on it would also be 62.4 lb.  But since the byoyant force is greater than its weight, pine will not stay underwater unless held there.

1. What is the density of the wood? 1($) lb/ft³ 
2. What is the density divided by the density of water? 2($)
3. Suppose a piece of oak wood flats with 62 percent of its volume underwater.  What is the density of the wood? 3($) lb/ft³

As in calculating pressure, we must  use the weight density rather than the mass density in calculations involving buoyancy.  Let us determine the apparent weight in water of a 5-cm³ piece of aluminum-about pencil size.  (The specific gravity of aluminum is 2.7) 

1. what is the weight density of aluminum in N/m³? 1($) N/m³
2. what is the weight density in N/cm³? 2($) N/cm³
3. how much does the piece of aluminum weigh? 3($) N
4. what is the weight density of water in SI units? 4($) N/m³
5. cover this to N/cm³ 5($) N/cm³
6. what is the buouant force of 5 cm³ aluminum? 6($) N
7. what is the apparent weight of the aluminum in water? 7($) N

What is the primary physical cause of the upward buoyant force experienced by an object when it is submerged in a fluid?

A completely submerged solid block has a total physical volume of \(1.5\text{ ft}^3\). What volume of water does it displace?

According to Archimedes' principle, the magnitude of the upward buoyant force acting on a submerged object is directly equal to which of the following properties?

Water has a weight density of approximately \(62.4\text{ lb/ft}^3\). If a solid cube with a volume of \(2\text{ ft}^3\) is held completely underwater, calculate the upward buoyant force acting on it.

Answer = 1($)

A heavy stone block weighs \(150\text{ lb}\) in the air. When it is completely submerged underwater, it displaces a volume of water that weighs \(50\text{ lb}\). What is the apparent weight of the stone block while it is underwater?

Answer = 1($)

Match the net force conditions below to the resulting mechanical behavior of an object placed in a fluid.

Match the net force conditions below to the resulting mechanical behavior of an object placed in a fluid.

A block of wood weighing \(35\text{ lb}\) is dropped into a lake. It breaks the surface and then comes to rest, floating stably. What is the exact value of the upward buoyant force acting on the wood while it floats?

An unknown solid material has a mass density that is strictly less than the mass density of the liquid it is dropped into. Fill in the placeholder to complete the statement detailing the behavior of the solid:

Because its density is lower than the fluid, the object will 1($) to the surface.

Determine if the following scientific statement is true or false:

"As a fully submerged solid iron ball sinks deeper and deeper into a deep body of water, the upward buoyant force acting on it increases drastically due to the rising water pressure."

A solid block of steel sinks straight to the bottom of a pool. However, if the same amount of steel is rolled thin and shaped into a hollow boat hull, it floats easily. Why does altering the geometric shape allow the steel to float?