Advertisements
Advertisements
Question
Answer the following in detail.
List four methods of magnetizing a magnetic substance.
Advertisements
Solution
Methods of magnetizing a magnetic material are :
- Single-touch method – A magnet is rubbed along the magnetic substance from one end to another.
- Double-touch method – Opposite poles of two magnets are placed next to each other at the centre of the magnetic substance and rubbed in opposite direction along it.
- Magnetizing by induction – It is a method to make temporary magnets under the influence of a magnetizing force. The magnetic properties disappear when the influence of the magnetizing force is removed.
(A permanent magnet is brought close to the magnetic substance but not touched.) - Electric current – A magnet made by using electric current is called an electromagnet. It is a temporary magnet and stops behaving like a magnet when the current is stopped. Electromagnets can become permanent magnets if certain materials like steel and special alloys are placed in a coil and a very strong current is passed through the coil.
APPEARS IN
RELATED QUESTIONS
You are given a magnet. How will you use it to find north-south direction at a place?
Explain the meaning of the term magnetic field ?
How are the magnets kept safely? What is the role of keepers in storing the magnets?
Bar magnets are often stored in pairs as shown in the figure. E and F being pieces of metal.
What is the material of darkened part?
Write a short note on lighting conductors.
With the help of a diagram explain the following:
Magnetisation of steel needle using electric current such that the pointed end should have north polarity.
The south pole of a bar magnet and the north pole of a U-shaped magnet will _______.
MRI stands for _______.
What will happen when we place magnets near cell phones, computers, and DVDs?
What are the factors that determine the strength of the magnet?
