Electricity & Magnetism + Temperature, Thermal Energy, and Heat

electromagnetism consists of two components of energy called:

electricity and magnetism

each can be used to create the other

How can electricity be generated to power a lightbulb?

• something spins the generator

• as the magnet inside the generator rotates, it causes electrons/a charge to build up on the coil

• electrons want to bond to other atoms to “ground out”

• give them a conductor like copper wiring

• before it can ground out, we pass it through a lightbulb

• inside the lightbulb is a filament often made of a metal that provides resistance, making it harder for electrons to travel through

• as electrons push, creating friction, creates heat, gets hot enough that it glows, creating light

• then electrons pass through and go to another line, which is the neutral line that takes electricity back to ground out

Electrons will take the path of…

least resistance

Electrolysis

a method of separating ions within a substance by passing electrical current through the substance

separate compounds into positive and negative ions

Electrolysis involves the use of two electrodes called

cathode and anode

anode

positive charge node (attracts negative ions)

cathode

negative charge node (attracts positive ions)

Temperature

the measure of the kinetic energy in a substance’s molecules. Simply put, temperature is atomic motion.

the hotter a substance is…

the faster its atoms move and the further apart they get

unlike temperature, the amount of thermal energy depends on

the quantity of a substance

ie a bathtub at 90 degrees has more thermal energy than a cup of coffee at 120 degrees

Conduction

occurs when heat is transferred due to fast moving atoms and molecules colliding with slower ones in a neighboring region

• usually in solids

• ie spoon in a bowl of hot soup, you can feel the heat at the spoon handle, molecules bump up through handle

Convection

occurs when cooler portions of a liquid or gas flow in to take the place of hotter, rising portions

• usually liquids and gases

• ex: in a pot of boiling water, the hot water at the bottom near flame rises up to take the cold waters place, pushing the cold water down, resulting in the churning boiling water

Radiation

occurs when heat is transmitted in the form of electromagnetic waves

high intensity

ie the sun radiating heat and nuclear reactions

A magnetic field surrounds ________ and is strongest at ________.

a magnet; the poles

When the north poles of two magnets are brought together what happens?

they reject each other, therefore the space in between them is the weakest point

What happens when opposite poles on a magnet are brought together?

they attract each other, forming a strong magnetic field between the two magnets