At a certain location, wind is blowing steadily at 10 m/s. Determine the mechanical energy of air per unit mass and the power generation potential of a wind turbine with 80-m-diameter (D) blades at that location. Take the air density to be 1.25 kg/m3. The mechanical energy of air per unit mass is kJ/kg. The power generation potential of the wind turbine is kW.

Explanation:

v = Velocity of wind = 10 m/s

A = Swept area of blade =

d = Diameter of turbine = 80 m

= Density of air =

Wind energy per unit mass of air is given by

The mechanical energy of air per unit mass is

Power is given by

The power generation potential of the wind turbine is .

the minimum amperage that the current in this wire would have to have so that its weight is completely supported by the magnetic force due to earth's field, assuming that no other forces except gravity act on it

pythagoras' theorem

square root (-5^2+9^2)

square root (25+81)

square root (106)

angle is tan^-1(9/5)

neg x, pos y