magnetism & electromagnetism electric current & magnetic fields chapter 1 section 3
TRANSCRIPT
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