electricity and ohm’s law

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2. Electric Current Electric current is a measure of the amount ofelectrical charge transferred per unit time. It representsthe flow of electron through a conductive material Electric current is similar to acurrent of water, but electriccurrent flows in solid metal wiresso it is not visible. Electric current can carry a lot ofpower..tQI 3. ELECTRIC CURRENT An ELECTRIC CURRENT exists whenever electric charge flowsthrough a region, e.g., a simple light bulb circuit. The magnitude of the current is measured in AMPERES (Amps/A) 1 ampere = 1 coulomb/second 4. Electric Circuits An electric circuit is something that provides acomplete path through which electricity travels. Wires in electric circuits are similar in someways to pipes and hoses that carry water. 5. Electric Circuits 6. VoltageVoltage is the electrical force, or"pressure", that causes current to flow in acircuit. Voltage is measured in volts (V). A voltage difference of 1 volt means 1 amp ofcurrent does 1 joule of work in 1 second. 7. Electrical Resistance Resistance measures how difficult it is for currentto flow. The total amount of electrical resistance in a circuitdetermines the amount of current that in the circuit for agiven voltage. The more resistance the circuit has, the less current thatflows. The SI unit of resistance is the ohm (). One ohm is the resistance when avoltage of 1 volt is applied with a currentof 1 amp. 8. Ohms Law Georg Simon Ohm (1787-1854), A Germanphysicist, discovered Ohms law in 1826. Statement of Ohms LawThe current through a conductor is proportional to thepotential difference between its ends, provided thetemperature of the conductor remains constant. 9. Ohms Law Georg Ohm showed that the flow of an electric currentthrough a wire depended on its resistance and thepotential difference between its endsA graph drawn between the voltmeter readings and ammeterreadings, shows a straight line pattern. The straight lineindicates a relationship and is named as ohms law.Expressed mathematically, 10. Ohms Law: Resistance AndResistors The ratio of voltage to current is called theresistanceIn many conductors, the resistance is independentof the voltage; this relationship is called Ohmslaw. 11. Electrical Resistor Resistor is used to control the amount of current flowing in acircuit The two main types of resistors : Wire-wound (coil of fine wire) resistors Composition (carbon) resistorsElectric resistance is the ratio of one volt and one ampere.Or We can say that Ohm is the unit of Electric resistance. Electrical components called resistors can be used to controlcurrent. 12. Ohms LawOhms law gives a relationship between the voltage (V), current(I), and resistance (R) as follows:V = I R 13. The EndCall us for moreinformationwww.iTutor.com1-855-694-8886Visit