ELECTRICITY

L IGHTNING RODS Lightning rods are a metal pole which is erected on the top a a building, it is then connected to conductive wire which passes through the building and buried in the ground. This “earths” the electricity. Buildings need them because they are higher than anything around them, and lightning will strike the closes conductive surface with the lowest resistance. If a lightning bold was to strike a building it would most probably blow out all of the power appliances if they are not protected. When the lightning rod is erected on the top of the building the lightning will hit it and travel to the ground, which will have no effect on the building.

BENJIMAN FRANKLIN Benjamin Franklin attached a key to his kite which was then attached to another string which ran into a metal can. He did this to show that the key would earth the lightning bolt and keep him safe. He attached a key to the string because the key was conductive and would channel the electricity down to the ground. He found out that electricity can be earthed by another, conductive path.

LIGHTNING Lightning kills 5-10 Australians per year. Causes more than 100 injuries in Australia per year. INDURIES: Direct strike (approximately 3-5% of injuries) Side splash from another object (approximately 30% of injuries) Contact voltage from touching an object that is struck (approximately 1-2% of injuries) Ground current effect as the energy spreads out across the surface of the earth when lightning hits a distance away from the person (approximately 40-50% of injuries) Upward leader that does not connect with the downward leader to complete a lightning channel (approximately % of injuries)

INDURIES Lightning injury is a neurologic injury, affecting all 3 parts of the nervous system. Brain – Neurocognitive changes, sleep disturbance, personality change, seizures, learning disability, postconcussive headaches, nausea, attention deficit, distractibilityBrain – Neurocognitive changes, sleep disturbance, personality change, seizures, learning disability, postconcussive headaches, nausea, attention deficit, distractibility Autonomic nervous system - Regulation of blood pressure and cardiac response, GI insult, impotence, sympathetically mediated pain syndromes Peripheral nervous system - Chronic pain, sensory problems

Florida is known as the "Lightning Capital of the World” this is because it had the most deaths and injuries caused by lightning Deaths and Injuries. If you are:Then: In a forest -Seek shelter in a low area under a thick growth of small trees. In an open area -Go to a low place such as a ravine or valley. Be alert for flash floods. On open water-Get to land and find shelter immediately. Anywhere you feel your hair stand on end (which indicates that lightning is about to strike)-Squat low to the ground on the balls of your feet. Place your hands over your ears and your head between your knees. Make yourself the smallest target possible and minimize your contact it the ground. DO NOT lie flat on the ground.

ELECTRIC ANIMALS Because electricity is easily conducted in water, most electric animals are fish. They use electrical signals to protect themselves, attract mates, find prey, and navigate. Electric fish, like the electric ell, electric catfish, electric ray and the electric elephant fish in Africa, are electrogenic. This means that they emit charges from special electric organs in their bodies. These fish are also electro receptive, which means that they can detect electrified, letting them distinguish their own species from other species. They generate their electricity by opening a ion channel which allows posetivly charged sodium to flow through, revercing the charge momentarily. By causeing a sudden difference in voltage it generates a current.

BIBLIOGRAPHY overview