Magnetism + Charges

Magnet

An object that has two poles

What is a magnet made from?

Nickel, cobalt, iron, or bismuth

What is the unit used for magnet fields

TESLA

The poles of a magnet?

North and South poles

Two like poles?

repel

Two unlike poles

attract

Can you ever have a monopole?

No! Magnets are dipoles

Unmagnetized

No relationship at all to the movement, magnetic domains are randomly arranged

Magnetized

They all go the same direction o

Objects all have small areas called _____?

domains

Magnetic Field lines are ____?

imaginary

What are Magnetic Field lines?

Lines that show the forces of attraction or repulsion around the poles of a magnet

What do the field lines look like?

Field lines go out of North and into South

What does field lines look like around two like magnetic poles?

They repel from eachother, out of north

What does field lines look like around two unlike magnetic poles?

Attract eachother, out of north and into south

Magnetic flux

flux is stronger at the poles (more field lines, more strength, more flux)

Electric flux

It is essentially the "flow" of electric field lines through a surface

Temporary magnets

When you can make something magnetized even if it is not normally a magnet

How can you magnetize an object?

Hold the object next to a magnetized object or run electricity over it.

Electrons

Negatively charged particles

Protons

Positively charged particles

The elementary charge

An elementary charge is just one electron or one proton (q)

q =

1.6 ×10- 19 C

Electrostatics

Study of charges that are at rest

Electricity

When charges are moving

Conductors

Have a free electron and allow electricity to flow through the material (e.x. Copper)

Insulators

Do not have a free electron and do not allow current to flow easily through the materials (e.x. Wood or Wool)

Charging by friction

Process that results in transfer of electrons between 2 objects that are rubbed together (e.x. Animal fur and Plastic)

electroscope

a device that can be used to determine if an object is charged or not

How does lightning happen?

Lighting occurs if there is wind in the clouds. Wind charges clouds due to friction. Cloud is now filled with charges that are trying to repel so they eventually MOVE to find protons.

Charging by Conduction

Process of taking a charged object and touching it to a neutral object..

Current will flow…

until they are the same charge

Charging by Induction

Process in which a neutral object is charged by becoming CLOSE to a charged object

Coulombs law

Obviously a force that is acting between charged object and Coulombs law allows us to find the force acting on them

Coulomb’s law equation

F = kqq’/d²

K =

(constant) 9 × 10^9 Nm²/C²

Force between two charges is a?

vector force