Home
Class 12
PHYSICS
The magnetic moment of a short bar magne...

The magnetic moment of a short bar magnet is `1*6Am^2`. It is placed in the magnetic meridian with north pole pointing south. The neutral point is obtained at `20cm` from the centre of the magnet. Calculate the horizontal component H of earth's field. If magnet be reversed i.e. north pole pointing north, find the position of the neutral point.

Text Solution

Verified by Experts

Here, `M=1*6Am^2`,
`d_1=20cm=1/5m, H=?`
When north pole of magnet is pointing south, neutral points lie on axial line of magnet. At neutral point, `B_1=(mu_0)/(4pi)(2M)/(d_1^3)=H`
or `H=(10^-7xx2xx1*6)/((1//5)^3)=4xx10^-5tesla`
When magnet is reversed i.e., north pole is pointing north, neutral points lie on equatorial line of the magnet. We have to calculate `d_2`.
As `B_2=(mu_0)/(4pi)(M)/(d_2^3)=H :. d_2^3=(mu_0)/(4pi)M/H`
`d_2^3=(10^-7xx1*6)/(4xx10^-5)=0*4xx10^-2m^3`
`=0*4xx10^-2xx10^6cm^3=4000cm^3`
`d_2=(4000)^(1//3)=15*87cm`
Promotional Banner

Topper's Solved these Questions

  • MAGNETIC EFFECT OF CURRENT AND MAGNETISM

    PRADEEP|Exercise Conceptual Problems (d)|2 Videos

  • MAGNETIC EFFECT OF CURRENT AND MAGNETISM

    PRADEEP|Exercise Very Short Answer Questions (a)|2 Videos

  • ELECTROSTATICS

    PRADEEP|Exercise ASSERTION-REASON TYPE QUESTIONS|2 Videos

  • OPTICS

    PRADEEP|Exercise Multiple choice questions|1 Videos

Similar Questions

Explore conceptually related problems

A 10 cm long bar magnet of magnetic moment 1.34 Am2 is placed in the magnetic meridian with its south pole pointing geographical south. The neutral point is obtained at a distance of 15 cm from the centre of the magnet. Calculate the horizontal component of earth’s magnetic field.

A short bar magnet is placed in magnetic meridian with its north pole pointing toward south: Its magnetic moment is 2Am^(2) . Neutral point is obtained 10cm from centre of magnet toward north. Calculate horizontal component of earth's magnetic field.

A short bar magnet of magnetic moment 1.2Am^(2) is placed in the magnetic meridian with its south pole pointing the north. If a neutral point is found at a distance of 20cm from the centre of the magnet, the value of the horizontal component of the earth's magnetic field is

A 30 cm long bar magnet is placed in the magnetic meridian with its north pole pointing south. The neutral point is obtained at a distance of 40 cm from the centre of the magnet. Pole strength of the magnet is (The horizontal component of earth’s magnetic field is 0.34 Gauss)

A short bar magnet is placed in the magnetic meridian with its north pole pointing towards geographical south. A neutral point is found at a distance of 30 cm from the centre of the magnet. If the horizontal component of earth's field is 0.4G , calculate the magnetic moment of the magnet .

A bar magnet 30cm long is placed in magnetic meridian with its north pole pointing south. The neutral point is observed at a distance of 30cm from its centre. Calculate the pole strength of the magnet. Given horizontal component of earth's field is 0*34G .

A short bar magnet of magnetic moment 0*5JT^-1 is placed with its magnetic axis in the magnetic meridian, with its north pole pointing geographic north. A neutral point is obtained at a distance of 0*1m from the centre of the magnet. Find the horizontal component of earth's magnetic field.

A short bar magnet is placed with its north pole pointing south. The neutral point is 10cm away from the centre of the magnet. If H=0*4 gauss, calculate magnetic moment of the magnet.