Chapter 14 : Magnetism

Question 1

Give the definition for a magnetic field

Answer 1

a region in space i which a magnet of ferromagnetic material experiences a magnetic force

Question 2

Give the definition for a pole

Answer 2

A region of high concentration of magnified lines

Question 3

Give the definition of a magnetic domain

Answer 3

a region inside a magnetic that contains billions of atoms and each atom behaves like a small magnet

Question 4

Give the definition for hysteresis

Answer 4

The tendency of a material to maintain its magnetic properties

Question 5

Give the definition for Curie Temperature

Answer 5

A maximum temperature at which materials lose their magnetic characteristics

Question 6

Give 5 properties of magnetic field lines

Answer 6

• invisible
• 3D
• Non-contact repulsion / attraction force
• Direction always from the North pole to the South pole
• The denser the magnetic field the string the magnetic field ( densest at the poles therefore strongest at the poles )

Question 7

Go over drawing a magnetic field

Answer 7

😛

Question 8

TRUE / FALSE

when a magnet is broken, the new little pieces create nee north and south poles

Answer 8

TRUE

Question 9

why does a compass always point north?

Answer 9

The compass needle points north because the north pole of the magnet inside is attracted to the south pole of Earth’s built-in magnet

Question 10

compass needle points to the earth’s magnetic north

Answer 10

🙇🏽‍♀️

Question 11

Describe the angle of inclination (3)

Answer 11

• Magnetic N is 11° left of the rotation axis and magnetic S is 11° right if the rotation axis
• The 11° difference is called the angle of inclination

Question 12

name 4 importance’s of the earths magnetic field

Answer 12

• Birds navigated by making use of earth’s magnetic field during migration
• earth’s magnetic field traps charged particles that are blown towards the upper atmosphere of the earth by solar wind from the sun
• charged particles can damage telecommunications
• charged particles travel along the magnetic field lines of the earth until they get close to the earth’s magnetic poles -> here they collide with air molecules causing = aurora

Question 13

name 3 ferromagnetic material

Answer 13

• iron
• nickel
• cobalt

Question 14

describe the magnetic domains in an unmagnetized ferromagnetic material and a magnetized

Answer 14

• unmagnetized -> domains are aligned in different directions-> magnetic field is 0
• magnetized -> domain aligns itself with the external magnetic field

Question 15

what is hard iron

Answer 15

keeps its magnetic characteristics for a long time ; often used in permanent magnets

Question 16

what is soft iron

Answer 16

easily magnetized and unmagnetized

domain aligns itself quickly and can easily swing outta the parallel arrangement

Question 17

what is curie temperature

Answer 17

maximum temperature at which materials lose their magnetic characteristics
- kinetic energy that is transferred causes the magnetic domain to move out of arrangement or out of line

Question 18

how do you store a permanent magnets?

Answer 18

stored at room temperature

Question 19

how do you store bar magnets?

Answer 19

stored parallel to each other with opposite poles facing each other

Question 20

DO NOT DROP OR HAMMER MAGNETS

Answer 20

the domains will be unaligned