17 resistance in series and parallel
- 1. Resistance in series and parallel
- 2. Resistance in series Example 1: The circuit drawn below shows one source of electrical potential, VT, and three resistors R1 (16 ) , R2 (27 ), and R3 (12 ) connected in series. 16 Ω 27 Ω 12 Ω VT What is the overall resistance of the circuit?
- 3. Resistance in series For series circuits: Rs = R1 + R2 + R3 + …etc. series This is called finding the equivalent resistance, Rs. It’s like combining all the resistors into one big resistor.
- 4. Resistance in series Example 1: What is the overall resistance of the circuit? 16 Ω 27 Ω 12 Ω VT Rs = (16 Ω) + (27 Ω) + (12 Ω) Rs = 55 Ω
- 5. Resistance in parallel Example 2: Find the equivalent resistance when a 4.0 bulb and an 8.0 bulb are connected in parallel 4.0 Ω 8.0 Ω
- 6. Resistance in parallel For parallel circuits: 1 1 1 1 etc. Rp R1 R2 R3 parallel This is called finding the equivalent resistance, Rp. It’s like combining all the reciprocal of all resistors into one big resistor.
- 7. Resistance in parallel Example 2: Find the equivalent resistance when a 4.0 bulb and an 8.0 bulb are connected in parallel 1 = 1 + 1 Rp R1 R2 1 = 1 + 1 4.0 Ω Rp (4.0 Ω) (8.0 Ω) Find common denominator 1 = 2 + 1 Rp 8.0 Ω 8.0 Ω 8.0 Ω 1 = 3 Rp 8.0 Ω Rp = 8.0 Ω FLIP!!! 1 3 Rp = 2.7 Ω
- 8. Current, Voltage, & Resistance in Series and Parallel Solve for the unknown values in this circuit: It = 0.5 A I2 = ? I1 = 0.25 A V2 = ? Vt = 6.0 V R2 = ? V1 = ? Rt = ? R1 = ?
- 9. Current, Voltage, & Resistance in Series and Parallel Solve for the unknown values in this circuit: It = 0.5 A I2 = ? 0.25 A I1 = 0.25 A V2 = ? V 6.0 Vt = 6.0 V V R2 = ? 1 V1 = ? V 6.0 Rt = ? I1 R1 = ? 1 V Rt = Vt R2 = (6.0V) It I1 (0.25A) R1 = (6.0V) Rt = (6.0V) (0.25A) R2 = 24 Ω (0.5A) R1 = 24 Ω Rt = 12 Ω Check your answer by checking the resistance
- 10. Current, Voltage, & Resistance in Series and Parallel Check your answer by checking the resistance Rt = 12 Ω R1 = 24 Ω R2 = 24 Ω 1 = 1 + 1 Rt R1 R2 1 = 1 + 1 (12 Ω) (24 Ω) (24 Ω) Find common denominator 2 = 1 + 1 24 Ω 24 Ω 24 Ω
Editor's Notes
- #2: http://www.youtube.com/watch?v=tU1UKn7iXv8 (peeing on an electric fence)