A force, such as friction, that operates opposite the direction of motion of a body and tends to prevent or slow down the body's motion. A measure of the degree to which a substance impedes the flow of electric current induced by a voltage. Resistance is measured in ohms.
What is a tornado? A tornado is a violent rotating column of air extending from a thunderstorm to the ground. The most violent tornadoes are capable of tremendous destruction with wind speeds of up to 300 mph. They can destroy large buildings, uproot trees and hurl vehicles hundreds of yards. They can also drive straw into trees.
Since a tornado is a spinning column of air with an axis of rotation, the tornado itself is a vortex. Some tornadoes also contain smaller vortices call suction vortices. Theseâ¦ vortices circle with the rotation of the main vortex and carve curved paths of more severe damage within the main damage path. A tornado with such features is called a multiple vortex tornado.