PHY 04 Lesson 5: Magnetic Poles, Magnetic Force and Magnetic Field

Magnetism

The force exerted by magnets when they attract or repel each other.

Motion and alignment

This causes some parts of magnetic force

Magnesia

place in greece where magnets were found

Magnetite

Magnetic mineral that takes on Earth's magnetic polarity as it crystallizes.

Magnet

any material that attracts iron and materials that contain iron, metal with a strong attraction to another metal

Ferromagnetic Materials

possess some unpaired electrons and become strongly magnetic in an external magnetic field, and has the ability to be magnetized uniform

Iron, Cobalt, Nickle, Steel

Types of magnetic metals

Aluminum, Copper, Silver, Gold

Types of non-magnetic

Neodymium magnet/metal

The strongest permanent magnets commercially available. They are very brittle and will crack under stress.

Demagnetization

Reduction or removal of magnetic properties from a magnet.

Heating magnet to very high temperature

Dropping and hammering of magnet that causes vibration

Bringing magnet in contact with like poles repeatedly

Self-demagnetization - Over time loses magnetism

Methods of Demagnetization

Magnetization

Process of making a material magnetic.

Permanent Magnet

Made from a magnetized material with its own persistent magnetic field.

Temporary Magnet

Made of soft metals that retain their magnetism only when near a permanent magnetic field.

Electromagnet

The magnetic field is produced by an electric current, made of coils.

Magnetic Field

a region around a magnetic material or a moving electric charge within which the force of magnetism acts.

Electromagnetism

the interaction of electric currents or fields and magnetic fields.

Electrostatic force

attraction or repulsion of particles or objects because of their electric charge.

right hand rule

Common method used to determine the direction of the magnetic force vector. Thumb points in the direction of charge's velocity, fingers point in direction of magnetic (B) field, palm points in the direction of the acting force.

Upward current

Counterclockwise magnetic field

Downward current

Clockwise magnetic field

Solenoid

A coil of wire that produces a magnetic field when carrying an electric current

Electromagnetic Inducation

When a conductor and a magnetic field more relative to each other

Electromagnetic Force

a force associated with charged particles, which has two aspects, electric force and magnetic force

Magnetic Flux

the measurement of the total magnetic field lines that pass through a surface

Faraday's Law

The magnitude of the induced e.m.f. is directly proportional to the rate of change of magnetic flux linkage

A charge in the magnetic field of a coil of wire will induce/produce on EMF/voltage in the coil

Generator

converts mechanical energy into electrical energy

Transformer

A device that increases or decreases the voltage of alternating current