1. Parallel Circuits Thursday, April 18, 2015

2. Unit 9: Electricity Thursday, 2/18 Respond to the following What happens to the current as it moves through a series circuit? Upcoming dates Tuesday, 2/16 – Series circuit quiz – moved to Thursday, 2/18 Thursday, 2/17 – Parallel circuit quiz – moved to Monday, 2/22 Monday, 2/22 – Circuit design due Wednesday, 2/24 – Unit quiz - moved to Friday moved to Friday, 2/26 Friday, 2/26 – Electricity Test and last day to turn in unit missing work – moved to Tuesday, 3/1 Thursday, 3/3 – Magnetism quiz – moved to Monday, 3/7 Friday, 3/4 – 3NWS Extra credit due by 4:00 PM Friday, 3/11 – End of the 3NWS

3. Unit Overview Types of Electricity Dynamic Static Direct Current (DC) Alternating Current (AC) Series ComplexParallel

4. Circuit – In Series Only one path

5. Circuit – In Parallel More than one path

6. What do you think? If a circuit has multiple branches will the voltage, resistance, and current behave differently? Write your thoughts in your notes.

7. Parallel 1. reciprocal of the total resistance is the 1. reciprocal of the total resistance is the sum of the reciprocals of the separate sum of the reciprocals of the separate resistors resistors 1/R T = 1/R 1 + 1/R 2 +1/R 3 +... 2. total current is the sum of the current through each resistor through each resistor I T = I 1 + I 2 + I 3 +... 3. potential difference is the same across each resistor each resistor V T = V 1 = V 2 = V 3 =... In other words, in a parallel circuit, resistance adds as reciprocals, voltage stays the same, and current splits. In other words, in a parallel circuit, resistance adds as reciprocals, voltage stays the same, and current splits.

8. Kirchhoff’s Rules Junction Rule: the sum of all currents entering the junction must equal the sum of all currents leaving the junction.

10. Practice