P4.3 - Potential Difference And Resistance (Finished) Flashcards
What is current measured din?
Amperes, A
What is the formula linking potential difference, current and resistance?
Potential difference = current * resistance
What is the formula that links potential difference, energy transferred and charge?
Potential difference across a component = energy transferred (J) * charge (C)
What is resistance caused by?
Electrons passing through a (e.g. bulb) have to push their way past lots of vibrating atoms. These atoms resist the passage of electrons through the component.
What is an ohmic conductor?
Ohmic conductors are conductors that don’t change in resistance as current changes, provided a constant temperature
At a constant temperature, how can the curent flowing through an ohmic conductor be found?
At a constant temperature, the current flowing through an ohmic conductor is directly proportional to the potential difference across it
What dare some examples of ohmic conductors?
Wires, resitors
What does ohms law state?
Ohms law states that the current flowing through a resistor at a constant temperature is directly proportional to the potential difference across it