Magnestism

Question 1

Ferromagnetic materials

Answer 1

Substances that can be magnetized and attracted to magnets

Question 2

Magnetic fields

Answer 2

A region in space in which a magnet or ferromagnetic material experiences a magnetic force

Question 3

Properties of magnetic field lines

Answer 3

• they are continuous
• never cross or touch each other
• are more concentrated here the field strength is the greatest
• run from north to south
• they are three dimensional

Question 4

Magnetic domain

Answer 4

Small region of millions of atoms where the magnetic direction is the same

Question 5

Curie temperature

Answer 5

The temperature above which a magnet loses its magnetic properties

Question 6

How are magnetic fields produced

Answer 6

By moving charge (the electrons inside the atoms of the magnet)

Question 7

Hard iron

Answer 7

A type of iron that has a strong magnetic field and can retain its magnetization even when removed from an external magnetic field

Question 8

Hard iron domain

Answer 8

Domains are not easily aligned but remain aligned for a long period of time

Question 9

Hard iron magnet type

Answer 9

Permanent magnet

Question 10

Soft iron

Answer 10

A type of iron that has a weak magnetic field and loses its magnetization when removed from an external magnetic field

Question 11

Soft iron domain

Answer 11

Domain is easily magnetized but magnetism is lost quickly

Question 12

Soft iron magnet type

Answer 12

Electromagnets

Question 13

Compass

Answer 13

Has a small, lightweight needle which is free to move in a horizontal plane around a pivot point. The needle of a compass is magnetized so that the one end points to Earths magnetic north pole and the other to the south pole

Question 14

Geographic north pole

Answer 14

Point in the northern hemisphere where the rotational axis meets the earth’s surface

Question 15

Magnetic north pole

Answer 15

Point in northern hemisphere where the magnetic field lines enter the earth. Point is constantly changing

Question 16

Solar wind

Answer 16

A stream of charged particles (mainly positively charged protons and negatively charged electrons) coming from the sun

Question 17

Earths magnetic field protects earth from:

Answer 17

Solar winds and geomagnetic storms

Question 18

Geomagnetic storms formation

Answer 18

In addition to usual solar wind, the sun may eject a large bubble of material (protons and electrons) with its own magnetic field from the outer atmosphere. Sometimes these bubbles travel towards the earth where their magnetic fields can join with earths magnetic field. When this happens, a huge amount of energy is released into the Earth’s magnetosphere, causing a geomagnetic storm.

Question 19

Northern lights

Answer 19

Aurora Borealis

Question 20

Southern lights

Answer 20

Aurora Australis

Question 21

Polar auroras formation

Answer 21

When charged particles from the solar wind reach the Earth’s magnetosphere, they spiral along the magnetic field lines towards the North and South poles. If they collide with particles in the Earth’s atmosphere, they can cause red or green lights which stretch across a large part of the sky which is called the aurora.