static electricity electrical charge: is a concentration of electricity

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  • Slide 1
  • Static Electricity Electrical Charge: Is a concentration of electricity
  • Slide 2
  • Unlike Charges Attract one another
  • Slide 3
  • Like Charges Repel one another
  • Slide 4
  • Electric Fields The effect an electric charge has on other charges in the space around it.
  • Slide 5
  • Strength of Electric Field Amount of charge that produces the field Amount of charge that produces the field And the distance from the charge And the distance from the charge
  • Slide 6
  • Static Electricity and Charging Static electricity: is the study of the behavior of electric charges, including how charge is transferred between objects.
  • Slide 7
  • Charges can be Transferred Friction Friction Contact Contact Induction Induction
  • Slide 8
  • Charging by Friction Transferring of electrons
  • Slide 9
  • Charging by Contact Charging by contact occurs when someone actually touches another object and the electrons are then transferred (Van de Graaf Generator)
  • Slide 10
  • Charging By Induction A transfer of charge without contact between materials.
  • Slide 11
  • Static Discharge Occurs when a pathway through which charges can move forms suddenly. An example would by lightning.
  • Slide 12
  • Electric Current & Ohms Law
  • Slide 13
  • Electric Current The rate at which charges flows through the lamp or wires. The rate at which charges flows through the lamp or wires. Current: is how much electric charge flows past a pint in a circuit during a given time. Current: is how much electric charge flows past a pint in a circuit during a given time. Current is measured in ampes. Current is measured in ampes.
  • Slide 14
  • Two Types of Current Direct Current (DC) Direct Current (DC) Alternating Current (AC) Alternating Current (AC)
  • Slide 15
  • Direct Current Charge flows in one direction Charge flows in one direction An example would be a flashlight or most battery powered devices. An example would be a flashlight or most battery powered devices.
  • Slide 16
  • Alternating Current Is a flow of electric charge that regularly reverses its direction. Is a flow of electric charge that regularly reverses its direction. Electric current in your home and schools are like this. Electric current in your home and schools are like this.
  • Slide 17
  • Conductors and Insulators Electrical Conductor Electrical Conductor Electrical Insulator Electrical Insulator
  • Slide 18
  • Electrical Conductor Is a material through which charge can flow easily Is a material through which charge can flow easily For example: copper; silver; and most metals For example: copper; silver; and most metals
  • Slide 19
  • Electrical Insulator A material through which a charge cannot flow through easily. A material through which a charge cannot flow through easily. For example: Wood; Plastic; rubber; and air For example: Wood; Plastic; rubber; and air
  • Slide 20
  • Resistance Is the opposition to the flow of charges in a material. Is the opposition to the flow of charges in a material. The S.I. unit of resistance is Ohm. The S.I. unit of resistance is Ohm. A materials thickness, length, and temperature affect its resistance. A materials thickness, length, and temperature affect its resistance.
  • Slide 21
  • Superconductor Is a material that has almost zero resistance when it is cooled to low temperatures. Is a material that has almost zero resistance when it is cooled to low temperatures. The best superconductor so far is cooled to 138 K. The best superconductor so far is cooled to 138 K.
  • Slide 22
  • Voltage In order for charge to flow in a conducting wire, the wire must be connected in a complete loop that includes a source of electrical energy. In order for charge to flow in a conducting wire, the wire must be connected in a complete loop that includes a source of electrical energy.
  • Slide 23
  • Voltage Potential Difference: is the difference in electrical potential energy between two places in an electrical field. Potential Difference: is the difference in electrical potential energy between two places in an electrical field. It is measured in joules per coulomb, or volts, it can also be known as voltage. It is measured in joules per coulomb, or volts, it can also be known as voltage.
  • Slide 24
  • Voltage Sources Batteries Batteries Solar Cells Solar Cells Generators Generators
  • Slide 25
  • Voltage Sources Battery: is a device that converts chemical energy to electrical energy. Battery: is a device that converts chemical energy to electrical energy. Have terminals that can connect to wires in a circuit. Have terminals that can connect to wires in a circuit. One terminal is positive and the other is negative. One terminal is positive and the other is negative.
  • Slide 26
  • Ohms Law Founded by German Scientist Georg Ohm. Founded by German Scientist Georg Ohm. First determined how resistance and current affect voltage. First determined how resistance and current affect voltage. Discovered that voltage is not the same everywhere in a circuit. Discovered that voltage is not the same everywhere in a circuit. Hypothesized that resistance reduces the voltage. Hypothesized that resistance reduces the voltage.
  • Slide 27
  • Ohms Law Ohms Law: the voltage (V) in a circuit equals the product of the current (I) and the resistance (R). Ohms Law: the voltage (V) in a circuit equals the product of the current (I) and the resistance (R). V = I x R or I = V/R V = I x R or I = V/R Increasing the voltage increases the current. Keeping the same voltage and increasing the resistance decreases the current. Increasing the voltage increases the current. Keeping the same voltage and increasing the resistance decreases the current.
  • Slide 28
  • Circuit Diagrams Electric Circuit: A complete path through which charge can flow. Electric Circuit: A complete path through which charge can flow. Ex. Wiring in a house Ex. Wiring in a house Circuit diagrams use symbols to represent parts of a circuit, including a source of electrical energy and devices that are run by the electrical energy. Circuit diagrams use symbols to represent parts of a circuit, including a source of electrical energy and devices that are run by the electrical energy.
  • Slide 29
  • Circuit Diagrams Circuit diagrams shows one or more complete paths in which a charge can flow. Circuit diagrams shows one or more complete paths in which a charge can flow.
  • Slide 30
  • Series Circuits Series Circuit: charge has only one path through which it can flow. Series Circuit: charge has only one path through which it can flow. Ex. Christmas Tree Lights Ex. Christmas Tree Lights If one element stops functioning in a series circuit, none of the elements can operate. If one element stops functioning in a series circuit, none of the elements can operate.
  • Slide 31
  • Parallel Circuits Parallel Circuit: is a electric circuit with two or more paths through which charges can flow. Parallel Circuit: is a electric circuit with two or more paths through which charges can flow. If one element stops functioning in a parallel circuit, the rest of the elements still operate. If one element stops functioning in a parallel circuit, the rest of the elements still operate.
  • Slide 32
  • Power & Energy Calculations Electric Power: the rate at which electrical energy is converted to another form of energy. Electric Power: the rate at which electrical energy is converted to another form of energy. The unit is Watt or joules per second The unit is Watt or joules per second Power is often measured in KiloWatts. Power is often measured in KiloWatts. Electric power can be calculated by multiplying voltage by current Electric power can be calculated by multiplying voltage by current
  • Slide 33
  • Power and Energy Calculations Electric Power Electric Power P (Watts) = I (Amps) x V (volts) P (Watts) = I (Amps) x V (volts)
  • Slide 34
  • Electrical Energy E = P x t E = P x t This equation is used to find the electrical energy used by an appliance. This equation is used to find the electrical energy used by an appliance.
  • Slide 35
  • Electrical Safety Correct wiring, fuses, circuit breakers, insulation, and grounded plugs help make electrical energy safe to use. Correct wiring, fuses, circuit breakers, insulation, and grounded plugs help make electrical energy safe to use.
  • Slide 36
  • Home Safety Fuses: prevents current overload in a circuit. Fuses: prevents current overload in a circuit. Circuit Breakers: is a switch that opens when current in a circuit is too high. Circuit Breakers: is a switch that opens when current in a circuit is too high.
  • Slide 37
  • Personal Safety Grounding: when the electric takes a shorter path to a wire which leads to the ground. This is a transfer of excess charge through a conductor. Grounding: when the electric takes a shorter path to a wire which leads to the ground. This is a transfer of excess charge through a conductor.