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Here are some graphics for the ohm’s law lesson. Read through the book, work out the assigned problems, and come up with a lesson plan (written on paper) for this unit.
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Here are some graphics for the ohm’s law lesson. Read through the book, work out the assigned problems, and come up with a lesson plan (written on paper) for this unit. I have a box of resistors that you could pass around, and a setup where you can change resistance and voltage and watch a light bulb get dimmer or brighter. I will have already taught them about current (I = q/t)
+ - Symbols A Cell. + and -, Infinite current, R = 0, what’s really inside A Battery of cells A resistor A voltmeter, R = infinity V3 An ammeter, R = 0 A3
+ - A R • Ohm’s Law • V = Voltage (like pressure) • I = Current (like flow rate) A = ammeter – measures current V • R =V • I • R = Resistance in ohms () • V = Voltage in Volts (V) (pressure) • I = Current in Amps (A) (flowrate)
+ - A R • Ohm’s Law – re written for current • V = Voltage (like pressure) • I = Current (like flow rate) • R = Resistance to flow V • I =V • R • R = Resistance in ohms () • V = Voltage in Volts (V) (pressure) • I = Current in Amps (A) (flowrate)
+ - A Black 0 Brown 1 Red 2 Orange 3 Yellow 4 Green 5 Blue 6 Violet 7 Gray 8 White 9 Gold 5% Silver 10% No color 20% R Ohm’s Law V • I =V • R • R = Resistance in ohms () • V = Voltage in Volts (V) (pressure) • I = Current in Amps (A) (flowrate) • They don’t need to know the color code • Demo - pass around resistors • (two properties - power and resistance) • Demo - power supply, resistor, light bulb • (show increase/decrease V, and R)
Ohm’s Law + - A 120. mA 12.0 V • R =V • I • R = Resistance in ohms () • V = Voltage in Volts (V) (pressure) • I = Current in Amps (A) (flowrate) R= ?? Example 1:
Ohm’s Law + - A 120. mA 12.0 V • R =V • I • R = Resistance in ohms () • V = Voltage in Volts (V) (pressure) • I = Current in Amps (A) (flowrate) R= ?? Example 1:
Whiteboards – you need about 6 because they are so simple 1 | 2 | 3 | 4 | 5 | 6
A light bulb has a resistance of 1200. Ω, and is hooked up to 240. volts. What current flows through it? • Given: • R = V • I • R = 1200 Ω • V = 240 V • I = ? • I = V/R = 240/1200 = 0.20 A = 200. mA 0.200 A of 200. mA
question goes here • Given: • R = V • I • R = • V = • I = • Put your solution here answer goes here
question goes here • Given: • R = V • I • R = • V = • I = • Put your solution here answer goes here
question goes here • Given: • R = V • I • R = • V = • I = • Put your solution here answer goes here
question goes here • Given: • R = V • I • R = • V = • I = • Put your solution here answer goes here
question goes here • Given: • R = V • I • R = • V = • I = • Put your solution here answer goes here