/0/ Electric Circuits Do Light Bulb Demo Electric Circuits here are two different types of electrical circuits. Series Parallel Series Circuit: Circuit in which a current flows through each component, one after another. here is only one path for the current to follow. One Path and More than path 4 Current Because there is only one path for electrons to travel in a series circuit. he current at any one point in the circuit would be equal to the current at any other point in the circuit. = = = =... he current through each resistor is the same. esistance Once again because there is only one path in a series circuit, for the case of resistance this means that each electron will have to go through every resister with in the circuit. herefore the total resistance is the sum of all the resistors found in the circuit. = + + +...
/0/ Potential Difference (oltage) n a series circuit the total voltage drop across the entire circuit is equal to the sum of the individual voltage drops across each resister. 4 + 4+ = n the picture above, the skate boarder has a drop in gravitational potential energy at each stage during the trip. his is very similar the drop in electric potential energy (voltage) in a series circuit as an electron passes through a resister. 7 = + + +... 8 What would the potential difference be across the second resister? 4 olt Drop http://www.stmary.ws/highschool/physics/home/animations/electricity/circuits_bigger.swf 9 Find the total current in the circuit below. = + + +... =.0+ 4.0=.0Ω = = Four loads (.0 S,.0 S, 7.0 S, and 9.0 S) are connected in series to a volt battery. a) Find the equivalent resistance of the circuit. 4 S b) Find the total current in the circuit. 0.0 A c) Find the potential difference across the 7.0 S load. = =.A.
/0/ Parallel Circuit: Circuit in which there are two or more paths for the current to flow. Here s A hought Picture walking through a crowded building, and there are that many people that you can hardly move. hen the hallway splits into two hallways of the same size. Half the people go one way and the other go the other way. Now you have much more room because there are only half as many people in the hallway. What would happen if the hallway was to split again? And again? Would you have more and more room to walk each time? f you have more room would it be easer for you to walk down the hallway? Could you say that there is less resistance to your motion? his is what happens within a parallel circuit, the more paths that electrons have to chose from, the less over all resistance there is to their motion. 4 Find the total resistance of the given parallel circuit n a parallel circuit the total resistance can be found by the following formula = + + +... = + + +... 0Ω f each resister is Ω, then we get = 0 + 0 + 0Ω 0 = + +. 0Ω = 0 + 0 + 0 = 0 = = 9.4 8. = Ω = 0Ω Because the current had equivalent paths to chose from the Not how the total resistance is smaller over all resistance is / of what it would have been otherwise. than any of the individual resistors. n a parallel circuit the total current is equal to the sum of all of the individual currents through each branch of the circuit n a parallel circuit the total current is equal to the sum of all of the individual currents through each branch of the circuit A A = + + +... A A 7 8
/0/ What n would a parallel the circuit voltage be across the total a resister voltage that is was the hooker same up as at the any Hook Measure location voltage up between the a wire across voltage to the each two each anywhere wires? individual terminal between resistor. the two wires = = = =... ake a volt battery. http://www.stmary.ws/highschool/physics/home/animations/electricity/circuits_bigger.swf 9 Find the total current of the given parallel circuit = + + +... = = = 0 = = = 40 = = = 0. 0. 0. Solve the following circuit. = 0.+ 0.+ 0. = 0.9A = = = = volts = + + +... 8= 4+ 4+ = A = = = Ω = = = = = = 4A 4A A 0 battery is connected to four loads (.0 S,.0 S,.0 S, and.0 S) in parallel. a) Find the equivalent resistance of the circuit..4 S b) Find the total current leaving the battery. 4.0 A c) Find the current through the.0 S load. A 4 4
/0/ DO Pg. 79 # s 7 (pdf 89) Pg. 74 # s (pdf 89) Complex Circuit: A complex circuit is one that has both series and parallel components at the same time. Despite their name, the method for working with complex circuits is quit easy. We simplify the circuit into a smaller less complicated circuit, one section at a time. he first thing we see here is different series circuits (which can be simplify) embedded within the complex circuit. Find the equivalent resistance of the circuit below. Now we have a plane parallel circuit that we can easily work with. Step : Combine the resisters that are in parallel. 8 = 40 + 40 = 40 = = Ω = 8+ + = 40Ω Step : Combine the resisters that are in series. 9 Step : Combine the resisters that are in parallel. 0
/0/ = 40 + 40 = 40 = = Ω DO Pg. 78 # s & 7 (pdf 89) Pg. 7 # s -7 (pdf 89) HS Handout Do Your Ohm Work Step 4: Combine the resisters that are in series. = + = 40Ω