DE -- Fluids Density Pressure

Why are liquids, gases, and plasmas considered fluids?

• less thermal energy

• greater thermal energy

• they occupy more space than solids

• they resist shearing forces

The major distinction between gases and liquids --

• gases more easily compress but liquids do not

• liquids easily flow but gases do not

• gases easily flow but liquids do not

• the molecular structure of liquids is ordered and structured

Select all units of pressure.

• psi

• Pa

• N/m²

• m/s/s

Fluid pressure has no direction, being a scalar quantity.

• True

• False

The forces due to pressure have well-defined directions: they are always exerted ______________ any surface.

• inside of

• perpendicular to

• parallel to

• adjacent to

The pressure from the water beneath the swimmer is greater than the pressure above. Why?

• buoyant forces

• shearing forces

• static forces

• kinetic forces

Diving into a pool, you feel the weight of pressure. Where does this pressure come from?

• the air above you

• the water above you

• both the air and the water above you

Why does the dam increase in thickness at the bottom compared to the top?

• to balance the shearing forces from the water at depth

• to balance the increasing force due to the increasing pressure at depth

• to increase the resistant forces of static pressure from denser water at depth

Tags

NGSS.MS-ETS1-1