Buoyancy Density and Pressure

How do we calculate density? (with correct units!)

• D = m/v (in g/mL or g/cm3)
• D = v/m (in g/mL or g/cm2) 
• D=m/v (in mL/g or cm3/g) 

Buoyancy is the tendency for objects to float in a fluid. We consider buoyancy the...

• Un-gravity force

• The upward force

• Gravitational pull

• Downwards pull on an object

Pressure at the bottom of the ocean is greatest because:

• The water is most dense at the bottom.
• The water is least dense at the bottom.
• The water is buoyant at the bottom.

If the mass of an object is greater than the buoyant force, the object will:

• Float
• Sink

When you hold an object in the water,

• Water is displaced and rises
• Water is displaced and decreases
• The buoyant force pushes down on the object

When you increase your depth under water, the water pressure on your body

• increases

• decreases

• stays the same

How do you Calculate Pressure

• Force(N)/Area(m²)

• Force(kg)/Area(mi²)

• Area(m²)/Force(N)

Pressure can be measured in Pascals (Pa) or Newtons per square metre.
1 Pa = 1N/m2

• True
• False

Density is defined as...

• Centimeters cubed per mass of substance
• Mass per unit volume of a substance
• Flow rate of a substance

Tags

NGSS.MS-PS1-2

Archimedes' Principle states that... 

• The buoyant force acting on an object equals the volume of the fluid displaced by the object. 
• The buoyant force acting on an object equals the weight (force of gravity) of the fluid displaced by the object.
• The buoyant force acting on an object will always be equal.