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Hard magnetic materials like tungsten-steel alloy or chromium-steel alloy are used in the manufacture of:

Hard magnetic materials like tungsten-steel alloy or chromium-steel alloy are used in the manufacture of: Correct Answer permanent magnets

  • Generally, ferromagnetic materials are used for making permanent magnets. These materials include tungsten-steel alloy or chromium-steel alloy iron, nickel, cobalt, and some rare earth metals.
  • Steel is an alloy of iron and so can also be made into a permanent magnet. Alloys with less iron, nickel, or cobalt will be magnetically soft and have a weaker magnetic field.
  • Alnico (made of Aluminium, Nickel, and Cobalt) is also used for making a permanent magnet.

Important Points

High-Frequency transformer Core:

  • Ferrites materials have a tendency to hold the magnetic flux within their core.
  • Ferrite is a ceramic compound consist of Iron oxide mixed with zinc, nickel and manganese compounds.
  • The ferrite core offers high resistance (or low electrical conductivity) which decreases the magnitude of eddy current, so losses reduce.
  • The ferrite core reduces magnetostriction noises.

 

Permanent Magnets:

  • Permanent magnets are magnets that retain their magnetism over long periods of time. Permanent magnets are made of hard ferromagnetic materials.
  • In a paramagnetic material, every individual atom (or ions or molecules) possesses a dipole moment.
  • And this magnetic moment of every atom interacts with one another in such a way that they spontaneously align themselves in a common direction over a macroscopic volume which is termed as the domain.
  • The magnetic strength of a magnetic material is inversely proportional to temperature, since as temperature increases because of thermal agitation orientation of atoms becomes random when leading to a decrease in its magnetic field, and after certain temperature magnetic material loses its magnetic property permanently.
  • Also, Temporary magnets are those which act like a permanent magnet when they are within a strong magnetic field but lose their magnetism when the magnetic field disappears. E.g. Electromagnet.

Related Questions

Consider the following statements: 1. Both ferromagnetic and ferrimagnetic materials have domain structures; each domain has randomly oriented magnetic moments when no external field is applied. 2. Both ferromagnetic and ferrimagnetic materials make those domains that have a favourable orientation to the applied field grow in size. 3. The net magnetic moment in ferromagnetic materials is higher than that in ferrimagnetic materials. 4. The net magnetic moment in ferrimagnetic materials is higher than that in ferromagnetic material. Which of the above statements are correct?
Consider the following statements regarding hysteresis loops of hard and soft magnetic materials: 1. Hysteresis loss of hard magnetic material will be less than that of soft material 2. Coercivity of hard material will be greater than that of soft material 3. Retentivity of the two materials will always be equal Which of these statements are correct?
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Fact 1: All dogs like to run.
Fact 2: Some dogs like to swim.
Fact 3: Some dogs look like their masters.

If the first three statements are facts, which of the following statements must also be a fact?
I: All dogs who like to swim look like their masters.
II: Dogs who like to swim also like to run.
III: Dogs who like to run do not look like their masters.
An alloy A contains two elements, copper and tin in the ratio of 2 : 3, whereas an alloy B contains the same elements in the ratio of 3 : 4. If 20 kg of alloy A, 28 kg of alloy B and some more pure copper are mixed to form a third alloy C which now contains copper and tin in the ratio of 6 : 7, then what is the quantity of the pure copper mixed in the alloy C?
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In a group, 22 women like Red color, 20 women like the blue color and 19 women like Yellow color. Among them, 5 women like both Red and Blue color, 5 women like both Yellow and Blue color and 9 women like both Red and Yellow color. 14 women like only Blue color and 4 women all the three colors. Find the total number of women who like only Red color.
There are 90 people in a company, they all like at least one of the drinks namely tea, coffee, and milk. Further it is known that, 20 people like all the three drinks. 30 people like both coffee and milk, 25 people like both tea and milk and 35 people like both tea and coffee. A total of 60 people like tea and a total of 40 people like milk. What is the number of people who like only coffee?
In a group, 22 women like Red colour, 20 women like blue colour and 19 women like Yellow colour. Among them, 5 women like both Red and Blue colour, 5 women like both Yellow and Blue colour and 9 women like both Red and Yellow colour. 14 women like only Blue color and 4 women all the three colors. Find the total number of women who like only Red color.