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Charging on!. 1.2 & 1.3 Charging by Contact & Induction and Lightning. TVO VIDEO SERIES: http://www.youtube.com/watch?v=OL9wcTBjDN0&list=PLdIVKwXe8Up9z0pJGe0oLY5-yLbsaz_b7 Electroscope : detects the presence of electric charges. Pith ball electroscope . Metal leaf electroscope. Charging.
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Charging on! 1.2 & 1.3 Charging by Contact & Induction and Lightning
TVO VIDEO SERIES: http://www.youtube.com/watch?v=OL9wcTBjDN0&list=PLdIVKwXe8Up9z0pJGe0oLY5-yLbsaz_b7 Electroscope: detects the presence of electric charges Pith ball electroscope Metal leaf electroscope
Charging... • By Contact: • Generating a charge on a neutral object by touching it with a charged object • Neutral object will have the same charge as the object charging it
Charging • By Induction: • Movement of electrons in a substance without direct contact with an object • The force is attractive
Electric Fields • The space around a charged object • The effect of its charge can be felt by other objects • The greater the charge, the stronger (and bigger) the field • Electric forces are transmitted at the speed of light Attraction Repulsion
Lightning! • Strong winds and collisions between water droplets and clouds cause electrons to be transferred and a charge to occur • Lower parts of clouds are negatively charged • Upper parts are positively charged
Lightning! • The large negative charge pushes away negative charges in the earth = Positive charge • Giant discharge = Lightning • heats air to 33000 degrees Celsius (hotter than sun) • Air molecules collide and produce thunder
Lightning Rods • A rod attached to a house that is connected to a buried cable or rod • If lightning strikes it will drain off into the ground without creating a fire in the house • Invented by Ben Franklin