Magnetism & Electromagnetism Electric Current & Magnetic Fields Chapter 1 Section 3

Magnetism & Electromagnetism

Electric Current & Magnetic Fields

Chapter 1

Section 3

Electric Charge

• Protons• “+”

• Electrons• “-”

Electric Current

• The measure of the amount of charge flowing past a given point each second

• Measurement for current– Ampere

• Amp, A

Electric Current

• Produces a magnetic field

• Changing the direction of the current changes the direction of the magnetic field

Electric Circuit

• A complete path through which electric charges can flow

Conductors & Insulators

• Conductor– Electrons are loosely

bound to atoms– Electrons can flow

• Metals

• Insulator– Electrons are tightly

bound to atoms– Electrons do not flow

• Plastics• Wood• Glass• Rubber

Resistor

• Uses electrical energy as it interferes (or resists) the flow of charge

• Produce…– Light– Heat

Lightbulbs

• Tungsten wire– Conducts electricity,

but heats up enough to glow

Superconductors

• A material that has no electrical resistance

• Repel magnets

• Occurs in some materials – very high temps– very low temps