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Connie's class
Unit 2 9/25 notes
Question | Answer |
---|---|
What is the first law of Electrostatics | Like charges repel, Unlike charges attract |
What is the second law of Electrostatics | Electrical charges reside only on the external surface of a charged object |
What is the third law of Electrostatics | Force between two charges is directly proportional to the product of their magnitudes and inversely proportional to the square of the distance bewteen them |
What is another name for the third law of Electrostatic | Coulomb's Law |
What are two types of Electrical currents | Alternating Current and Direct Current |
What is Alternating Current | Current that continuously changes direction (back and forth) as it moves through a substance |
What is Direct Current | Current that moves through a substance continously in the same direction |
What kind of states of matter can a negative charge move through | All states of matter (solids, liquids, and gages) |
What kind of states of matter can a positive charge move through | Liquids and gases |
What kind of charges can only move through solid materials | Negative (electrons) |
As current electricity moves through matter what does the charge encounter | Friction through contact with each other and contact with the atoms of the matter itself |
What is the friction between the charges and friction between currents and the atoms of the matter itself | Resistance |
What does the friction do to the current | Robs the current of some of its energy |
What will electrical charges (positive or negative) follow | The path of least resistance |
What are the electrical classifications of matter | Conductors, Insulators, Semiconductors, and Superconductors |
What is a conductor | Any substance which permits electrical charges to move very easily through that substance |
What are examples of conductors | Gold, Silver, Copper, and Aluminum |
What is an insulator | Any substance that blocks the flow of charges through the substance |
What are examples of insulators | Glass, Rubber, Plastic, and Wood |
What is a semiconductor | A substance that acts as a conductor under certain conditions ans as an insulator under other conditions |
What are examples of semiconductors | Germanium and Silicon |
What is a superconductor | A substance that has zero resistance when operated at extremely low temperaures |
What are examples of superconductors | Niobium and Titanium |
For 150 years after electricity was discovered in 1755 (by Benjarmin Franklin) how did people think that currents moved through a solid | It was theorized that electrical current moves through a solid from a positive to a negative point |
When was it determined that current moving in a solid actualy moves from negative to positive | In the 20th century |
What are the official names for the movement types | Concept of Conventional Flow, and Concept of Electron flow |
What is the Concept of Conventional Flow | Electricity moves from a positive to a negative ex. electricians |
What is the Concept of Electron Flow | Electricity moves from a negative to a positive ex. radiographers |
What is the Electron Flow concept used to described | Electrical current movement in radiologic equipment |
What do we reffer to as positive | Less negative |