Advertisements
Advertisements
प्रश्न
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.
उत्तर
Magnetic moment of the bar magnet, M = 0.48 J T−1
- Distance, d = 10 cm = 0.1 m
The magnetic field at distance d, from the centre of the magnet on the axis, is given by the relation:
B = `μ_0/(4pi) (2"M")/"d"^3`
Where,
μ0 = Permeability of free space = 4π × 10−7 T mA−1
∴ B = `(4pi xx 10^-7 xx 2 xx 0.48)/(4pi xx (0.1)^3)`
= 0.96 × 10−4 T
= 0.96 G
The magnetic field is along the S-N direction. - The magnetic field at a distance of 10 cm (i.e., d = 0.1 m) on the equatorial line of the magnet is given as:
B = `(μ_0 xx "M")/(4pi xx "d"^3)`
= `(4pi xx 10^-7 xx 0.48)/(4pi (0.1)^3)`
= 0.48 G
The magnetic field is along the N-S direction.
APPEARS IN
संबंधित प्रश्न
Distinguish between ‘paramagnetic’ and ‘ferromagnetic’ substances.
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]
Distinguish between diamagnetic and paramagnetic substances
A tangent galvanometer shows a deflection of 45° when 10 mA of current is passed through it. If the horizontal component of the earth's magnetic field is `B_H = 3.6 xx 10^-5 "T"` and radius of the coil is 10 cm, find the number of turns in the coil.
Answer the following question.
Write three points of differences between para-, dia- and ferromagnetic materials, giving one example for each.
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?
Magnetic material can be easily magnetized if magnetic susceptibility is ______.
The materials having negative magnetic susceptibility are ____________.
The magnetic property of magnetic substance is associated with ____________.
If a toroid uses bismuth for its core, will the field in the core be (slightly) greater or (slightly) less than when the core is empty?
Is the permeability of a ferromagnetic material independent of the magnetic field? If not, is it more for lower or higher fields?
A certain region of space is to be shielded from magnetic fields. Suggest a method.
Metals getting magnetised by orientation of atomic magnetic moments in external magnetic field are called ______.
If a charged particle at rest experience no electromagnetic force
- Assertion (A): Diamagnetic substances exhibit magnetism.
- Reason (R): Diamagnetic materials do not have a permanent magnetic dipole moment.
Explain the meaning of the following statement:
Curie temperature for soft iron is 770°C.