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.
Tornadoes are spawned from powerful thunderstorms, and cause fatalities and devastate neighborhoods in seconds. Tornadoes are rotating, funnel shaped clouds that extend from a thunderstorm to the ground, and generally occur near the trailing edge of a thunderstorm. Winds from a tornado can reach 300 miles per hour.