Fluid Fundamentals
Fighting Friction
Density Detectives
Atmospheric Pressure
Air Density & Performance
100

Air and water both belong to this category of matter.

What are fluids?

100

Fluid friction acting against a moving object is also called this.

What is drag?

100

Density compares an object’s mass to this measurement.

What is volume?

100

This instrument measures atmospheric pressure.

What is a barometer?

100

As air pressure increases, air density does this.

What is increases?

200

Fluids have no definite shape, so they take the shape of this.

What is their container?

200

Objects with this type of shape minimize resistance as they move through a fluid.

What are streamlined objects?

200

The mathematical formula used to calculate density.

What is density equals mass divided by volume? D=M / V

200

Atmospheric pressure does this as altitude increases.

What is decreases?

200

As air temperature increases, air density does this.

What is decreases?

300

This property describes a fluid’s resistance to changes in shape or motion.

What is viscosity?

300

As an object’s speed increases, fluid friction does this.

What is increases?

300

Two objects with equal volumes can have different densities when this property differs.

What is mass?

300

Name one unit used to measure atmospheric pressure.

What are inches of mercury, millibars, or pounds per square inch?

300

Increasing this measure of water vapor in the air slightly decreases air density.

What is humidity?

400

Honey moves more slowly than water because of this property.

What is higher viscosity?

400

Friction creates this layer of stagnant air along an airfoil.

What is the boundary layer?

400

Of air and water, this substance is more dense.

What is water?

400

This term describes the rate at which atmospheric pressure decreases as altitude increases.

This term describes the rate at which atmospheric pressure decreases as altitude increases.

400

Name the three atmospheric factors that affect air density.

What are pressure, temperature, and humidity?

500

This effect causes a moving fluid to attach to a surface and flow along it.

What is the Coanda effect?

500

Name three external characteristics of an object that affect fluid friction.

What are size, shape, and material?

500

Two substances have the same volume, but Substance A has twice the mass of Substance B. This substance is more dense.

What is Substance A?

500

For every 1,000-foot increase in altitude, atmospheric pressure decreases by approximately this amount.

What is 1 inch of mercury?

500

These three conditions combine to produce poor takeoff and climb performance.

What are high temperature, high altitude/low pressure, and high humidity?