Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
Concepts Of Physics MCQ Edition [Volume 2]PhysicsPermanent Magnets

In an oscillation magnetometer, a combination of two bar magnets completes 10 oscillations per second when their like poles are tied together, and 2 oscillations per second when their unlike poles are tied together. Determine the ratio of the magnetic moments of the two magnets, neglecting any induced magnetism.

Options

  1. A13 : 12
  2. B25 : 1
  3. C3 : 2
  4. D5 : 1

Correct answer

A. 13 : 12

Step-by-step solution

The frequency of oscillation in an oscillation magnetometer is given by f = 1 2 MB I , which implies f M for a constant moment of inertia I and magnetic field B . When like poles are tied together, the effective magnetic moment is M₁ + M₂ . The frequency is f₁ = 10 . When unlike poles are tied together, the effective magnetic moment is M₁ - M₂ . The frequency is f₂ = 2 . Taking the ratio of the frequencies: f₁ f₂ = M₁ + M₂ M₁ - M₂ Substituting the given values: 10 2 = M₁ + M₂ M₁ - M₂ 5 = M₁ + M₂ M₁ - M₂ Squaring bo

Practice Permanent Magnets on Quantrex Academy →

More from Permanent Magnets

The magnetic field at a point situated 10 cm from a magnetic dipole is observed to be 2.0 10⁻⁴ T . Calculate the magnetic moment of the dipole if this point is located in the broadThe magnetic field at a point due to a magnetic dipole is perpendicular to the magnetic axis. Find the angle that the line joining the point with the centre of the dipole makes witTwo long bar magnets are positioned such that their axes coincide and the north pole of the first magnet is located 2.0 cm away from the south pole of the second. Given that both mA long bar magnet possesses a pole strength of 10 Am . Determine the magnetic field at a point situated on the magnet's axis, at a distance of 5 cm from its north pole.A magnetic dipole having a magnetic moment of 1.44 A m ^2 is positioned horizontally such that its north pole points towards the north. Determine the location of the neutral point,A magnetic dipole having a magnetic moment of 0.72 2 A m ^2 is oriented horizontally such that its north pole points towards the east. Determine the position of a neutral point, giAssume the magnetic moment of the dipole at the earth's centre is 8.0 10²² A m ^2 . Determine the magnetic field B at the earth's geomagnetic poles. The radius of the earth is 6400Suppose the magnitude of the earth's magnetic field at the magnetic equator is 3.4 10⁻⁵ T . Find its value at the geomagnetic poles of the earth. Full Permanent Magnets list All Concepts Of Physics MCQ Edition [Volume 2] PYQs