As brightness of light increases, the resistance 20 (a) Ω decreases. 30 Ω 600 Ω As brightness of light 150 Ω increases, the current increases. (a) 40 Ω 300 Ω Any resistance greater than 3.3 kΩ. Resistors in Mixed Circuits Voltage Dividers (p39 41) – Resistors in Series (p34) (p36 38) – As its resistance As more resistors are (a) 44 increases, voltage across a Ω connected in series, the 30 resistor also increases. Ω total resistance increases. 75 Ω 600 As resistance Ω (a) 245 45 increases, electrons will Ω Ω 950 lose more energy as they Ω 830 (a) 108 pass through the resistor. Ω Ω 625 12 Therefore, the voltage Ω Ω 54 across the resistor will Ω (a) 550 24 increase. Ω Ω 6390 Ω (b) Is the lowest resistance (a) 125 Ω Resistors in Parallel (p35) 225 Ω 400 1.2 kΩ Ω As more resistors are connected in parallel, the 250 (a) Ω total resistance decreases. 300 Ω
As brightness of light increases, the resistance decreases. As brightness of light increases, the current increases. Any resistance greater than 3.3 kΩ. Resistors in Series (p34) As more resistors are connected in series, the total resistance increases. (a) 245 Ω 950 Ω 830 Ω 625 Ω (a) 550 Ω 6390 Ω Resistors in Parallel (p35) As more resistors are connected in parallel, the total resistance decreases. (a) 20 Ω 30 Ω 600 Ω 150 Ω (a) 40 Ω 300 Ω Resistors in Mixed Circuits (p36 – 38) (a) 44 Ω 30 Ω 75 Ω 600 Ω 45 Ω (a) 108 Ω 12 Ω 54 Ω 24 Ω (b) Is the lowest resistance 400 Ω Voltage Dividers (p39 – 41) As its resistance increases, voltage across a resistor also increases. As resistance increases, electrons will lose more energy as they pass through the resistor. Therefore, the voltage across the resistor will increase. (a) 125 Ω 225 Ω 1.2 kΩ (a) 250 Ω 300 Ω
Electricity-and-Energy-Problem-Booklet-St-Lukes.docx