During a lightning flash, there exists a potential difference of Vcloud - Vground = 2.5 x 109 V between a cloud and the ground. As a result, a charge of -21 C is transferred from the ground to the cloud.(a) How much work Wground–cloud is done on the charge by the electric force?(b) If the work done by the electric force were used to accelerate a 1100-kg automobile from rest, what would be its final speed?(c) If the work done by the electric force were converted into heat, how many kilograms of water at 0 °C could be heated to 100 °C?

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

answer///terminator or twilight zone;

answerdmitry mendeleyev made a workable classification of the elements