06 Magnetism and Electromagnetism

Question 1

Name the three magnetic elements

Answer 1

• iron
• nickel
• cobalt

Question 2

What is the name for metals like steel?

Answer 2

Magnetic alloys

Question 3

Define: Magnetic field

Answer 3

The region where a agnetic force is felt

Question 4

like poles…

Answer 4

repel

Question 5

opposite poles…

Answer 5

attract

Question 6

Where are magnetic fields strongest and why?

Answer 6

• Strongest at the poles
• Because the field lines are closer

Question 7

What are domains in a magnet?

Answer 7

They are a region in which the magnetic fields of atoms are grouped together and aligned

Question 8

What are the 3 points to remember when drawing/ stating the formation of a uniform field?

Answer 8

• Lines are striaght
• Lines are parallel
• Lines are equlally spaced

Question 9

How doy ou plot a magnetic field? (With a magnet and a compass) (5 points)

Answer 9

1. Draw dot around magnet
2. Drow dot close to magnet
3. Place tail of plotting compass on dot
4. Draw dot at compass point
5. Repeat steps 3-4

Question 10

Define magnetically hard (3 points)

Answer 10

• High coercity
• High hysterisis
• Retains magnetisation (permanently magnetised)

Question 11

Define Magnetically soft: (4 points)

Answer 11

• Low coercity
• Low hysteresis loss
• Loses magnetation easily
• Ideal for transformer cores

Question 12

What is a transformer core? (Describe the peice of apparatus)

Answer 12

A static device that transmits power from one source to another through electromagnetic induction (has high magnetic permability)
[The round thing.]

Question 13

Magnetic field strength is _____ everywhere (fill the blank)

Answer 13

the same

Question 14

How does one make a uniform field?

Answer 14

Place 2 bar magnets close together