Question

The higher the altitude the more slowly windmills rotate at the same wind speed. Which one of the following is the best reason why the blades of windmills rotate More slowly in higher places at the same wind speed? 1. *

1 point

(a) The air is less dense as altitude increases.

(b) The temperature is lower as altitude increases.

(c) Gravity becomes less as altitude increases.

(d) It rains more often as altitude increases.

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Answer 1

Explanation:

The question is not entirely correct. Not all Wind turbines rotate slowly.

Small wind turbines rotate at relatively high speeds.

Large wind turbine do rotate around 20rpm or so. The reason is their size and aerodynamic loads.

To make a good wind turbine that can handle all types of wind loads over a period of 20 years, you need to build it with easily accessible materials (to handle the cost) and ensure that they are easily replaceable in case of failures. There are so many design constraints related to the turbine internal structures, which all contribute to the way turbines are designed.