Q 01/05

As of 2025, which country generates the most electricity from wind, ahead of the second-placed United States?

A) Germany

B) China

C) India

D) Denmark

Answer · why

B) China

China generates more wind electricity than any other country, with the United States second. Denmark leads on a different measure: wind supplies a big...

Q 02/05

Wind power climbs much faster than wind speed itself, so doubling the wind multiplies the available power by what factor?

A) Twofold

B) Fourfold

C) Eightfold

D) Sixteenfold

Answer · why

C) Eightfold

Eightfold, because power rises with the cube of wind speed and two cubed is eight. It is why developers chase the windiest hilltops and coasts: slight...

Q 03/05

How many blades do almost all large commercial wind turbines have?

A) Four

B) Two

C) Three

D) Six

Answer · why

C) Three

The standard design is a horizontal-axis machine with an upwind rotor on a tall tubular tower.

Q 04/05

What is the housing at the top of a wind turbine tower, holding the gearbox and generator, called?

A) Cowling

B) Rotor hub

C) Turret

D) Nacelle

Answer · why

D) Nacelle

Nacelle housings hold the gearbox, generator and brake, and the whole box swivels on top of the tower to keep the rotor facing the wind.

Q 05/05

Why are a wind farm's turbines set several rotor widths apart?

A) Each leaves a choppy wake

B) Birds need flying room

C) Generators would interfere

D) The ground would give way

Answer · why

A) Each leaves a choppy wake

Each leaves a choppy wake of slowed air, much like the trail of a ship, so a turbine parked close downwind would get weaker, rougher wind. Spreading t...