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प्रश्न
What kind of ferromagnetic material is used for coating magnetic tapes in a cassette player, or for building ‘memory stores’ in a modern computer?
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उत्तर
Ceramic is used for coating magnetic tapes in cassette players and for building memory stores in modern computers.
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संबंधित प्रश्न
An iron rod of the area of cross-section 0.1m2 is subjected to a magnetizing field of 1000 A/m. Calculate the magnetic permeability of the iron rod. [Magnetic susceptibility of iron = 59.9, magnetic permeability of vacuum = 4π x 10-7 S. I. unit]
The susceptibility of magnesium at 200 K is 1.8 x 10-5. At what temperature will the susceptibility decrease by 6 x 10-6?
Show diagrammatically the behaviour of magnetic field lines in the presence of (i) paramagnetic and (ii) diamagnetic substances. How does one explain this distinguishing feature?
Explain Curie’s law for a paramagnetic substance.
Draw magnetic field line when a (i) diamagnetic, (ii) paramagnetic substance is placed in an external magnetic field. Which magnetic property distinguishes this behaviour of the field line due to the substances?
Answer in brief.
Discuss the Curie law for paramagnetic material.
A paramagnetic gas has 2.0 × 1026 atoms/m with atomic magnetic dipole moment of 1.5 × 10−23 A m2 each. The gas is at 27°C.
- Find the maximum magnetization intensity of this sample.
- If the gas in this problem is kept in a uniform magnetic field of 3 T, is it possible to achieve saturation magnetization? Why?
The materials having negative magnetic susceptibility are ____________.
Above the curie temperature the susceptibility of ferromagnetic substance varies ____________.
A small quantity of paramagnetic liquid is taken in a watch - glass and kept on two dissimilar magnetic poles. The liquid ____________.
A short bar magnet has a magnetic moment of 0.48 J T−1. Give the direction and magnitude of the magnetic field produced by the magnet at a distance of 10 cm from the centre of the magnet on
- the axis,
- the equatorial lines (normal bisector) of the magnet.
A certain region of space is to be shielded from magnetic fields. Suggest a method.
A hydrogen atom is paramagnetic. A hydrogen molecule is
A long solenoid has 1000 turns per metre and carries a current of 1 A. It has a soft iron core of µr = 1000. The core is heated beyond the Curie temperature, Tc.
- The H field in the solenoid is (nearly) unchanged but the B field decreases drastically.
- The H and B fields in the solenoid are nearly unchanged.
- The magnetisation in the core reverses direction.
- The magnetisation in the core diminishes by a factor of about 108.
Explain quantitatively the order of magnitude difference between the diamagnetic susceptibility of N2 (~5 × 10–9) (at STP) and Cu (~10–5).
Magnetic susceptibility for a paramagnetic and diamagnetic materials is respectively ______.
Which of the following cannot modify an external magnetic field as shown in the figure?
Explain the Domain theory in brief.
