The power available from a wind turbine is calculated by the following equation: upper p equals one half upper a rho nu cubed where pequalspower [watts], aequalssweep area (circular) of the blades [square meters], rhoequalsair density [kilograms per cubic meter], and nuequalsvelocity [meters per second]. the world's largest sweep area wind turbine generator in spain has a blade diameter of 420 feet [ft]. the specific gravity of air is 0.00123. assuming a velocity of 30 miles per hour [mi/h] and the power produced is 5 megawatts [mw], determine the efficiency of this turbine.

potential energy is directly proportional to height.

more height = more potential energy.

greatest increase in height = greatest increase in potential energy

where are the points with the greatest increase in height ?

has to be c-e or d-e .

he made 11 calls in one day

electromagnetic shielding is the practice of reducing the electromagnetic field in a space by blocking the field with barriers made of conductive or magnetic materials. shielding is typically applied to enclosures to isolate electrical devices from their surroundings, and to cables to isolate wires from the environment through which the cable runs. electromagnetic shielding that blocks radio frequency electromagnetic radiation is also known as rf shielding.

the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

from wikipedia