MAGNATISM ( PHY) Flashcards
What are the two types of magnetic poles?
North pole (N pole) and South pole (S pole)
The two poles are fundamental to understanding magnetism.
What is the law of magnetism regarding like and unlike poles?
Like poles repel, unlike poles attract
This fundamental principle governs the interactions between magnets.
What is induced magnetism?
When a magnetic material becomes a magnet itself due to proximity to a magnet
This process can create temporary magnetism in certain materials.
What materials are considered magnetic?
Iron (steel), Nickel, Cobalt, neodymium and their alloys
Only these materials can be attracted by a magnet.
What is the difference between magnetic and non-magnetic materials?
Magnetic materials can be attracted by a magnet; non-magnetic materials cannot
Examples of non-magnetic materials include paper, wood, and copper.
What is a magnetic field?
A region in which a magnetic pole experiences a force
The magnetic field is essential for understanding how magnets interact with each other and with magnetic materials.
How can the direction of a magnetic field be determined?
By using a compass or iron filings
A compass aligns with the magnetic field lines, indicating direction.
How does the spacing of magnetic field lines represent field strength?
Closer lines indicate a stronger magnetic field; spaced-out lines indicate a weaker field
This visual representation helps in understanding the strength of the magnetic field.
What is the definition of a dipole in magnetism?
An atomic magnet with both a north and south pole
The concept of dipoles is crucial in understanding the behavior of magnets.
What is the difference between soft and hard magnetic materials?
Soft materials are easily magnetized but do not retain magnetism; hard materials retain magnetism for a longer time
Soft iron is an example of a temporary magnet, while steel is a permanent magnet.
Fill in the blank: The North pole of a magnet always points to _______.
geographical North
This characteristic is why magnets are used in compasses.
What methods can be used for magnetization?
Stroking, Electrical method, Magnetic induction
Each method has its own application and effectiveness.
What methods can be employed for demagnetization?
Hammering, Electrical method, Heating/Dropping/Rough Handling
These methods disrupt the alignment of magnetic domains.
What is an electromagnet?
A magnet that can be switched on and off by electric current
Electromagnets can have their strength adjusted by varying the current.
What are the uses of permanent magnets?
Used in magnetic compasses, door bells, refrigerators, dynamos, motors, loudspeakers, microphones, and more
They are essential in various applications across different fields.
What is the Earth’s magnetic field?
The Earth behaves like a small magnet, with magnetic south lying near the geographic north
This magnetic field is crucial for navigation and protection from solar winds.
True or False: Non-ferrous materials contain iron.
False
Non-ferrous materials do not contain iron, while ferrous materials do.
What happens to the magnetic field lines at the North and South poles of a magnet?
At the North Pole, field lines are directed away; at the South Pole, they are directed inwards
This pattern helps visualize the magnetic field around a magnet.
What is the consequence of using a soft iron core in an electromagnet?
It increases the strength of the electromagnet
Soft iron cores are effective in enhancing the magnetic field produced by the coil.
