A-LEVEL Physics: 5.2.1: Resistivity (SaveMyExams) Flashcards
All Materials have Some…
Electrical Resistance.
As Free Electrons Move Through a Metal Wire, they Collide with ___ which get in their way. What happens as a Result of this?
Ions. As a Result, they Transfer Some, or All, of their Kinetic Energy to Thermal Energy on Collision, which Causes Electrical Heating. Increased Resistance.
In Metal Wires, Since Current is the Flow of Charge, the Ions Resisting their Flow Causes…
Resistance.
Resistance = …
Resistivity * Length / Area
R = ρ L/A
The Resistivity Equation Shows that: (2)
-The Longer the Wire, the Greater its Resistance.
-The Thicker the Wire, the Smaller its Resistance.
Doubling the Length of a Wire will…
Double the Resistance.
Doubling the Cross-Sectional Area of a Wire will…
Half the Resistance.
What is ‘Resistivity’?
Resistivity is an Intrinsic Property of a Material that Describes its Ability to Oppose the Flow of Electric Current Through it.
Resistivity is an Intrinsic Property of the Material, & is Dependent on…
Temperature.
Unit of Resistivity:
Ohmic Meters (Ω m)
The Higher the Resistivity of a Material, the Higher its…
Resistance.
Insulators have Such a High ___ that Virtually No ___ will Flow Through them.
Resistivity, Current.
