Question 1

After many variations and refinements, wind turbines _____ efficiency at converting wind energy into electricity.&#8203;&#10;A) &#8203;still do not exceed 25%&#10;B) can now exceed 50%&#10;C) offer 75%&#8203;&#10;D) provide 15%-35%

Accepted Answer

Over the years, wind turbines have undergone improvements and now have an efficiency rate that can exceed 50%. So, option B is the correct answer.

Question 2

&#8203;The best turbines today capture _____ of the wind's power.&#10;A) &#8203;at least 75%&#10;B) approximately 25%&#10;C) no more than 33%&#10;D) &#8203;more than 50%

Accepted Answer

According to current technology, the best turbines can capture more than 50% of the wind's power.

Question 3

Most modern wind turbines make use of aerodynamic lift.

Accepted Answer

Modern wind turbines typically use aerodynamic lift to rotate the blades and generate electricity. This lift is created by the shape and angle of the blades, similar to how airplane wings create lift.

Question 4

&#8203;A row of 25-foot-tall trees can produce turbulence unsuitable for wind turbines _____ feet away.&#10;A) &#8203;up to 100&#10;B) &#8203;more than 500&#10;C) up to 350&#8203;&#10;D) more than 1,000

Accepted Answer

The answer of &#8203;A row of 25-foot-tall trees can produce...

Question 5

&#8203;_____ must face into the wind to produce power and, therefore, require some mechanism to constantly realign the rotor during changes in wind direction.&#10;A) Horizontal-axis wind turbines&#10;B) Vertical-axis wind turbines&#10;C) &#8203;Multidirectional-axis wind turbines&#10;D) &#8203;Diagonal-axis wind turbines

Accepted Answer

Horizontal-axis wind turbines must face into the wind to produce power and require some mechanism to constantly realign the rotor during changes in wind direction. Vertical-axis wind turbines can operate regardless of wind direction as they have blades that rotate around a vertical axis, but they are less efficient than horizontal-axis turbines. Multidirectional-axis and diagonal-axis wind turbines are not commonly used and do not have established track records.

Question 6

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

Accepted Answer

Small wind turbines can provide a valuable source of energy for off-grid homes or farms, as they can generate electricity when there is a steady wind flow. However, the performance of small wind turbines can be affected by factors such as the location and surrounding environment, and they may not be as reliable or cost-effective as other renewable energy options like solar panels or hydropower.

Question 7

&#8203;_____ destroys lift by causing turbulence behind the blades.&#10;A) Pitching&#10;B) &#8203;Angling&#10;C) &#8203;Stalling&#10;D) &#8203;Blade wear

Accepted Answer

Stalling of the blades can cause turbulence, which disrupts the airflow over the blade and reduces lift.

Question 8

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

Accepted Answer

The amount of power captured by a wind turbine cannot exceed the amount of power available in the wind. In fact, due to the Betz limit and inefficiencies, wind turbines can only convert a fraction of the wind's power into electricity.

Question 9

&#8203;Moderate wind speeds _____ mph provide suitable power without overfatiguing components.&#10;A) &#8203;at least 5&#10;B) &#8203;gusting up to 30&#10;C) &#8203;in the range of 10-40&#10;D) &#8203;sustained at 40

Accepted Answer

Moderate wind speeds in the range of 10-40 mph provide suitable power without overfatiguing components.

Question 10

In the equation Power = ½ Av³, the represents _____ . A) rotor area B) kinetic energy C) wind speed D) density of air

Accepted Answer

In the given equation, the symbol $ \rho $ represents the density of air.

Question 11

&#8203;Operational wind speeds typically extend from _____ in residential-scale turbines.&#10;A) &#8203;6 mph to 40 mph&#10;B) 8 mph to 55 mph&#10;C) &#8203;10 mph to 60 mph&#10;D) 12 mph to 85 mph

Accepted Answer

The answer of &#8203;Operational wind speeds typically extend from _____...

Question 12

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

Accepted Answer

The answer of All types of wind turbines require high-quality...

Question 13

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

The answer of Propellers created during World War I were...

Question 14

Which of the following statements is true regarding commercial wind power?&#10;A) &#8203;It takes five years to offset the embodied energy of wind turbine construction.&#10;B) &#8203;Commercial wind power takes more time to implement than other renewable energy forms.&#10;C) &#8203;The environmental impact and impact on farming and ranching operations is significant.&#10;D) &#8203;Commercial wind power is currently the least expensive form of renewable energy.

Accepted Answer

The answer of Which of the following statements is true...

Question 15

_____ is the force of the air colliding with a surface.&#8203;&#10;A) &#8203;Drag&#10;B) &#8203;Lift&#10;C) &#8203;Pull&#10;D) &#8203;Friction

Accepted Answer

The answer of _____ is the force of the air...

Deck 8: Wind Power