Sustainable Energy: Wind

Question

A wind farm occupying a certain (unspecified) area in which the average wind speed is 3 metres per second (m/s) generates an average power of 5 kWh/d. If the wind speed is doubled to 6 m/s, what is the average power of the wind farm? You may assume that the original wind speed (3 m/s) and the doubled wind speed (6 m/s) are both above the "cut-in" wind speed and below the "rated" wind speed.

Answer 1

You should probably be using the rule that the power generated by a wind turbine is proportional to the CUBE of the wind speed. If the wind speed goes up by a factor of 2, what factor will the power go up by?