Advertisements
Advertisements
प्रश्न
A paramagnetic material is placed in a magnetic field. Consider the following statements:-
(A) If the magnetic field is increased, the magnetisation is increased.
(B) If the temperature is increased, the magnetisation is increased.
विकल्प
A and B are true.
A is true but B is false.
B is true but A is false.
A and B are false.
उत्तर
A is true but B is false.
If the magnetic field is increased, magnetisation of paramagnetic material placed in magnetic field is also increases. Hence, option (a) is correct.
Magnetization (I) is given by,
\[\overrightarrow{I} = \frac{\overrightarrow{M}}{V}\]
As the temperature is increased, magnetic moments of paramagnetic material becomes more randomly aligned due to incresed thermal motion. This leads decrease in the magnetization I.
APPEARS IN
संबंधित प्रश्न
The property of diamagnetism is said to be present in all materials. Then, why are some materials paramagnetic or ferromagnetic?
Can we have magnetic hysteresis in paramagnetic or diamagnetic substances?
When a ferromagnetic material goes through a hysteresis loop, its thermal energy is increased. Where does this energy come from?
A paramagnetic material is kept in a magnetic field. The field is increased till the magnetisation becomes constant. If the temperature is now decreased, the magnetisation ___________ .
A ferromagnetic material is placed in an external magnetic field. The magnetic domains ______________ .
The magnetic susceptibility is negative for _____________ .
The permanent magnetic moment of the atoms of a material is not zero. The material ________________ .
The permanent magnetic moment of the atoms of a material is zero. The material _________________ .
When a ferromagnetic material goes through a hysteresis loop, the magnetic susceptibility
(a) has a fixed value
(b) may be zero
(c) may be infinity
(d) may be negative
A rod is inserted as the core in the current-carrying solenoid of the previous problem. (a) What is the magnetic intensity H at the centre? (b) If the magnetization I of the core is found to be 0.12 A m−1, find the susceptibility of the material of the rod. (c) Is the material paramagnetic, diamagnetic or ferromagnetic?
Assertion: The earth¢s magnetic field is due to iron present in its core.
Reason: At a high temperature magnet losses its magnetism.
A dip circle is so set that its needle moves freely in the magnetic meridian. In this position, the angle of dip is 40º. Now the dip circle is rotated so that the plane in which the needle moves makes an angle of 30º with the magnetic meridian. In this position, the needle will dip by an angle ______.
The time period of oscillation of a magnet in a vibration magnetometer is 1.5 sec. The time period of oscillation of another magnet similar in size, shape and mass but having 1/4 magnetic moment than that of the 1st magnet oscillating at the same place will be ______.
The primary origin of magnetism lies in ______.
