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Electrodynamics
Question | Answer |
---|---|
Define electrodynamics. | The science of electric charges in motion. |
Under what conditions does an electric current consists of a flow of charged particles? | Gas, Ionic solution, Metallic conductor, Vacuum |
What are the two sources of electric current? | Cells/Batteries and Dynamo/Generator |
Define potential difference. | Difference in electrical potential energy between 2 points in an electric circuit. |
What is the UNIT of potential difference? | Volt |
Define volt. | Potential difference maintaining a current of ampere in a circuit whose resistance is 1 ohm. |
Define electromotive force. | The maximum difference of potential between the terminals of a battery. |
Define current. | Amount of electric charge flowing per second. |
What is the UNIT of current? | Ampere |
What is an ampere? | 1 coulomb quantity of electric charge flowing per second. |
Define resistance. | Property of circuit opposing or hindering flow of electric current. |
What is the UNIT of electrical resistance? | OHM |
Define OHM. | The resistance of a standard volume of mercury under standard conditions. |
On what factors does the resistance of a conductor depend? | Material, Length, Cross-sectional area, and Temperature |
Define dry cell. | Used in flashlights, consists of carbon rod surrounded by manganese dioxide, immersed in ammonium chloride paste, zinc chloride, water. |
Define wet cell. | Consists of hard rubber or plastic case containing sulfuric acid with immersed electrodes. |
How does temperature affect metal conductors? | The resistance becomes greater as the temperature rises. |
Define OHM's law. | The value of the current in a metallic circuit equals the potential difference divided by the resistance. |
Define ammeter. | Meter that measures in amperes. (in series) |
Define voltmeter. | Meter that measures, involts, the potential difference between any two points in a circuit. (in parallel) |
What is the unit of power? | Watt |
What is the equation for power loss? | P = I 2 R watts |
What is the formula that defines power loss in an electrical circuit? | P = I 2 R |
A gasoline engine will convert chemical energy to what type of energy? | Mechanical energy |
What type of charge moves in a conductor? | Negative charges |
What effect does a low temperature have on resistance? | Decreases |
What effect does a high temperature have on resistance? | Increases |
What is measured by a meter wired in series with a resistance? | Current |
Electric insulators inhibit movement of what? | Electric charge |