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Ch. 7, 8, 9
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Ch. 7 Electricity Electricity Electric Charge Positive and Negatives Conductors and Insulators Lightning Electric Current Circuits, Batteries, Ohm’s Law (I = V/R) Electric Energy
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Ch. 7 Electricity Electricity Electric Charge Positive and Negatives Conductors and Insulators Lightning
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Ch. 7 Electricity Bellringer WRITE the question. USE your book. What kind of charged particle is attracted to a positive charge? What is electric current made of? Define: Voltage Resistance Insulators
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Ch. 7 Electricity Electricity Electric Current Circuits, Batteries, Ohm’s Law (I = V/R) Voltage Difference is the force that causes electric charges to flow
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Ch. 7 Electricity Electricity Electric Current Circuits, Batteries, Ohm’s Law (I = V/R)
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Ch. 7 Electricity Electricity Ohm’s Law [I = V/R] Electrical Power [Power (watts) = IV]) Electrical Energy [E (kWh) = Pt] Current A flow of negatively charged electrons in one direction Measured in Ohms Follows a circuit (closed path) Parallel or Series Circuits Resistance Opposes the flow of electrons resulting in thermal energy and light Measured in Ohms
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Ch. 7 Electricity Electricity Ohm’s Law [I = V/R] Electrical Power [Power (watts) = IV]) Electrical Energy [E (kWh) = Pt] Current A flow of negatively charged electrons in one direction Measured in Ohms Resistance Opposes the flow of electrons resulting in thermal energy and light Measured in Ohms
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Ch. 7 Electricity Electricity Ohm’s Law [I = V/R] Electrical Power [Power (watts) = IV]) Electrical Energy [E (kWh) = Pt] Current A flow of negatively charged electrons in one direction Measured in Amps Follows a circuit (closed path) Parallel or Series Circuits Resistance Opposes the flow of electrons resulting in thermal energy and light Measured in Ohms Voltage The force that causes electrons to flow Measured in Volts Static Electricity Build up of excess charges on an object A sudden discharge of negatively charged electrons Lightning
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Problems to Solve 1. Calculate the voltage difference in a circuit with 25 ohms resistance if the current is 0.5 amps. 2. A current of 5 amps flows in a 600 watt light bulb. The voltage difference between the filament ends is 120V. What is the resistance of the filament?
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Problems to Solve 3. What kind of a circuit is this?
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Problems to Solve 2. What kind of a circuit is this?
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Problems to Solve 5. A toaster is plugged into an outlet where the voltage is 120V. How much power does it use if the current is 10A? 6. A VCR on powersave mode (not on) still uses 10 W of power. What is the current if the VCR is plugged into 220 V? 7. A flashlight bulb uses 2.4 W of power when the current in the bulb is.8 A What is the voltage difference supplied by the battery?
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Problems to Solve 8. A microwave with a power rating of 1,200 W is used for.25 h. How much electrical energy is used by the microwave? 9. A refrigerator operates for about 18 hours a day. The 700 W rating on a fridge means it uses ________ of electrical energy each day.
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Ch. 8 Magnetism Magnetic Poles
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Ch. 8 Magnetism
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The magnetic flux lines up the compass arrows along their North-South orientation
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Ch. 8 Magnetism
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What happens when the current is reversed?
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Ch. 8 Magnetism Electric Motors
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Ch. 8 Magnetism Electric Motors
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Ch. 8 Magnetism When electric current travels through a wire a magnetic field forms. Notice the change in direction. Why?
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Ch. 8 Magnetism When electric current travels through a wire a magnetic field forms. By forming many loops why is the magnetic field increased?
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Ch. 8 Magnetism When electric current travels through a wire a magnetic field forms. By forming many loops why is the magnetic field increased? http://science.howstuffworks.com/electroma gnet2.htm
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Ch. 8 Magnetism Successfully write and answer #1-13 p. 218 & #1-14, p. 250 In groups describe how an electrical generator works. Video answers.
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Ch. 8 Magnetism Remember the “Right Hand Rule” to determine the direction of the magnetic flux caused by a current.
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