Question 1

After many variations and refinements, wind turbines _____ efficiency at converting wind energy into electricity.​

Accepted Answer

A)  ​still do not exceed 25% 
B)  can now exceed 50% 
C)  offer 75%​ 
D)  provide 15%-35% B

Question 2

​_____ must face into the wind to produce power and, therefore, require some mechanism to constantly realign the rotor during changes in wind direction.

Accepted Answer

A)  Horizontal-axis wind turbines 
B)  Vertical-axis wind turbines 
C)  ​Multidirectional-axis wind turbines 
D)  ​Diagonal-axis wind turbines A

Question 3

​Moderate wind speeds _____ mph provide suitable power without overfatiguing components.

Accepted Answer

A)  ​at least 5 
B)  ​gusting up to 30 
C)  ​in the range of 10-40 
D)  ​sustained at 40 C

Question 4

Small wind turbines do not offer a valuable source of energy for off-grid homes or farms.

Accepted Answer

A) True 
 B)False

Question 5

Propellers created during World War I were used to make the first wind turbines, which generated electricity rather than milling grain or pumping water.

Accepted Answer

A) True 
 B)False

Question 6

All types of wind turbines require high-quality wind to generate electricity.

Accepted Answer

A) True 
 B)False

Question 7

_____ is the force of the air colliding with a surface.​

Accepted Answer

A)  ​Drag 
B)  ​Lift 
C)  ​Pull 
D)  ​Friction

Question 8

Which of the following statements is true regarding commercial wind power?

Accepted Answer

A)  ​It takes five years to offset the embodied energy of wind turbine construction. 
B)  ​Commercial wind power takes more time to implement than other renewable energy forms. 
C)  ​The environmental impact and impact on farming and ranching operations is significant. 
D)  ​Commercial wind power is currently the least expensive form of renewable energy.

Question 9

​_____ destroys lift by causing turbulence behind the blades.

Accepted Answer

A)  Pitching 
B)  ​Angling 
C)  ​Stalling 
D)  ​Blade wear

Question 10

​Operational wind speeds typically extend from _____ in residential-scale turbines.

Accepted Answer

A)  ​6 mph to 40 mph 
B)  8 mph to 55 mph 
C)  ​10 mph to 60 mph 
D)  12 mph to 85 mph

Question 11

Most modern wind turbines make use of aerodynamic lift.

Accepted Answer

A) True 
 B)False

Question 12

​The best turbines today capture _____ of the wind's power.

Accepted Answer

A)  ​at least 75% 
B)  approximately 25% 
C)  no more than 33% 
D)  ​more than 50%

Question 13

In the equation Power = ½ $ \rho $Av3, the $ \rho $ represents _____ .

Accepted Answer

A)  rotor area 
B)  kinetic energy 
C)  wind speed 
D)  ​density of air

Question 14

The amount of power captured by a wind turbine is significantly more than the amount of power available in wind.

Accepted Answer

A) True 
 B)False

Question 15

​A row of 25-foot-tall trees can produce turbulence unsuitable for wind turbines _____ feet away.

Accepted Answer

A)  ​up to 100 
B)  ​more than 500 
C)  up to 350​ 
D)  more than 1,000

Exam 8: Wind Power

After many variations and refinements, wind turbines _____ efficiency at converting wind energy into electricity.

_____ must face into the wind to produce power and, therefore, require some mechanism to constantly realign the rotor during changes in wind direction.

Moderate wind speeds _____ mph provide suitable power without overfatiguing components.

Small wind turbines do not offer a valuable source of energy for off-grid homes or farms.

Propellers created during World War I were used to make the first wind turbines, which generated electricity rather than milling grain or pumping water.

All types of wind turbines require high-quality wind to generate electricity.

_____ is the force of the air colliding with a surface.

Which of the following statements is true regarding commercial wind power?

_____ destroys lift by causing turbulence behind the blades.

Operational wind speeds typically extend from _____ in residential-scale turbines.

Most modern wind turbines make use of aerodynamic lift.

The best turbines today capture _____ of the wind's power.

In the equation Power = ½ $\rho$ Av³, the $\rho$ represents _____ .

The amount of power captured by a wind turbine is significantly more than the amount of power available in wind.

A row of 25-foot-tall trees can produce turbulence unsuitable for wind turbines _____ feet away.

Exam 8: Wind Power

After many variations and refinements, wind turbines _____ efficiency at converting wind energy into electricity.​

​_____ must face into the wind to produce power and, therefore, require some mechanism to constantly realign the rotor during changes in wind direction.

​Moderate wind speeds _____ mph provide suitable power without overfatiguing components.

Small wind turbines do not offer a valuable source of energy for off-grid homes or farms.

Propellers created during World War I were used to make the first wind turbines, which generated electricity rather than milling grain or pumping water.

All types of wind turbines require high-quality wind to generate electricity.

_____ is the force of the air colliding with a surface.​

Which of the following statements is true regarding commercial wind power?

​_____ destroys lift by causing turbulence behind the blades.

​Operational wind speeds typically extend from _____ in residential-scale turbines.

Most modern wind turbines make use of aerodynamic lift.

​The best turbines today capture _____ of the wind's power.

In the equation Power = ½ ρ \rho ρ Av3, the ρ \rho ρ represents _____ .

The amount of power captured by a wind turbine is significantly more than the amount of power available in wind.

​A row of 25-foot-tall trees can produce turbulence unsuitable for wind turbines _____ feet away.

After many variations and refinements, wind turbines _____ efficiency at converting wind energy into electricity.

_____ must face into the wind to produce power and, therefore, require some mechanism to constantly realign the rotor during changes in wind direction.

Moderate wind speeds _____ mph provide suitable power without overfatiguing components.

_____ is the force of the air colliding with a surface.

_____ destroys lift by causing turbulence behind the blades.

Operational wind speeds typically extend from _____ in residential-scale turbines.

The best turbines today capture _____ of the wind's power.

In the equation Power = ½ $\rho$ Av³, the $\rho$ represents _____ .

A row of 25-foot-tall trees can produce turbulence unsuitable for wind turbines _____ feet away.