Exams › JEE Main › Physics

Two identical magnetic dipoles, each having magnetic moment 1.0 A·m², are kept 2 m apart with their axes mutually perpendicular. The magnetic field at the midpoint between them is

1. 5 × 10⁻⁷ T
2. √5 × 10⁻⁷ T
3. 10⁻⁷ T
4. 2 × 10⁻⁷ T

Correct answer: √5 × 10⁻⁷ T

Solution

At the midpoint (1 m from each), one dipole gives an axial field 2*(1e-7)*m = 2e-7 T and the other an equatorial field (1e-7)*m = 1e-7 T. As the axes are perpendicular these add in quadrature: sqrt(4+1)*1e-7 = sqrt(5)*1e-7 T.

Related JEE Main Physics questions

• The SI unit Weber is used for measuring which of the following quantities?
• A material has relative permittivity εr and relative permeability μr. For a diamagnetic substance, which pair of values is physically permissible?
• A bar magnet freely suspended in the horizontal component of Earth’s magnetic field H has a time period of 4 s. If a second magnet is placed nearby and the time period becomes 2 s, then the magnetic field produced by the second magnet is:
• Which magnetic properties should the core material possess to be suitable for an electromagnet?
• A bar magnet has a length much greater than its width and thickness. In a vibration magnetometer, its oscillation period is 2 s. The magnet is then divided lengthwise into three equal pieces, and the three pieces are stacked together so that like poles are in contact. What is the oscillation period of this arrangement?
• A magnetic dipole is placed in two magnetic fields whose directions differ by 60°. If one field has magnitude 1.2 × 10⁻² T and the dipole settles in stable equilibrium making an angle of 15° with that field, what is the magnitude of the second field?

⚔️ Practice JEE Main Physics free + battle 1v1 →