Voltage Current and Resistance Ohms Law Lightning Strikes

Voltage, Current, and Resistance Ohm’s Law

Lightning Strikes https: //youtu. be/Ta. Pg. SWdc. Yt. Y

Voltage produces a flow of charge, or current, within a conductor. The flow is restrained by the resistance it encounters. When the ends of an electric conductor are at different electric potential energies, charge flows from one end to the other.

34. 1 Flow of Charge • Heat flows through a conductor when a temperature difference exists. Heat flows from higher temperature to lower temperature. • When temperature is at equilibrium, the flow of heat ceases.

34. 1 Flow of Charge • Heat flows through a conductor when a temperature difference exists. Heat flows from higher temperature to lower temperature. • When temperature is at equilibrium, the flow of heat ceases. Charge flows when there is a potential energy difference (voltage) between the ends of a conductor.

34. 1 Flow of Charge a. Water flows from higher pressure to lower pressure. The flow will cease when the difference in pressure ceases.

34. 1 Flow of Charge a. b. Water flows from higher pressure to lower pressure. The flow will cease when the difference in pressure ceases. Water continues to flow because a difference in pressure is maintained with the pump. The same is true of electric current.

34. 2 Electric Current Measuring Current Electric current is measured in amperes, symbol A. An ampere is the flow of 1 coulomb of charge per second. When the flow of charge past any cross section is 1 coulomb (6. 24 billion electrons) per second, the current is 1 ampere.

Measuring Current and Voltage https: //phet. colorado. edu/en/simulation/circuit-construction-kit-dc

Resistance is an object’s ability to resist or obstruct electric current from passing through it. All objects have some resistance to electric current —some more than others. The amount of resistance a certain object can supply is measured in “Ohms” and we use the Greek letter Ω to represent this. http: //phet. colorado. edu/en/simulation/resistance-in-a-wire

Voltage (V) Difference in potential energy Current (I) How quickly charge flows Resistanc e (Ω) How much the current is obstructed Measured in VOLTS V Measured in AMPS A Measured in OHMS Ω

Ohm’s Law Current is directly proportional to voltage.

Ohm’s Law Current is directly proportional to voltage. Current is inversely proportional to resistance.

Ohm’s Law Voltage causes current; resistance decreases current. http: //phet. colorado. edu/en/simulation/ohms-law

Ohm’s Law Voltage causes current; resistance decreases current. Put it together, and Ohm’s Law states: http: //phet. colorado. edu/en/simulation/ohms-law

Ohm’s Law Voltage causes current; resistance decreases current. Put it together, and Ohm’s Law states: http: //phet. colorado. edu/en/simulation/ohms-law

Ohm’s Law Example 1 A toaster with a resistance of 18 Ω is connected to an outlet (V=120 V). What is the current going through the bulb?

Ohm’s Law Example 2 One AA-battery (1. 5 Volts) is connected to a small bulb, resulting in a current of 0. 0075 A. What is the resistance of the bulb?