Presentation on theme: "ELECTRICITY REVIEW. Charges There are two types of charges- what are they? Positive and Negative Where do positive charges come from? Protons."— Presentation transcript:
Charges There are two types of charges- what are they? Positive and Negative Where do positive charges come from? Protons Where do negative charges come from? Electrons If an object gains electrons, what is its charge? Negative If an object loses electrons, what is its charge? Positive
Charges Predict what will happen if the following charges are brought close to each other. Positive and Negative Attract Positive and Positive Repel Negative and Negative Repel Negative and Positive Attract
Circuits What is voltage? The energy charges are given by a battery. What is current? The flow of electrons through a circuit. What is resistance? The prevention of charges to flow.
Ohm’s LawV=IR If a circuit is powered by a 9.0 V battery and there are 36 Ω of resistance, what is the current in the circuit? 9=I x 36I =.25 A If a second battery is added to the circuit, the voltage goes up to 18.0 V. If the resistance stays the same, what will happen to the current? 18=I x 36I =.50 AIt gets bigger (doubles) If the resistance is change and the current is now 0.75 A (still 18 V), what is the new resistance in the circuit? 18=.75 x R R=24 Ω
Circuit Types Is this a series or parallel circuit? Series What components make up the circuit? Three light bulbs and one battery If the first light bulb is unscrewed, what happens to the other light bulbs? They will still work because the other paths are still complete. If the battery was replaced with a 3 V battery, what would happen to the bulb brightness? They would get dimmer because there is less energy in the circuit. 6V6V
Circuit Types Is this a series or parallel circuit? Series What components make up the circuit? Light bulb, resistor, battery If the light bulb is unscrewed, what happens to the circuit? It stops working If another light bulb is added, what would happen to the brightness of the first bulb? It would get dimmer because there is even more resistance.
Drawings Draw a diagram of the circuit you see.