JEE Mains · Physics · STD 12 - 5. Magnetism and matter
Two identical small bar magnets each of dipole moment \(3\sqrt{5}\) J/T are placed at a center to center separation of \(10\) cm, with their axes perpendicular to each other as shown in figure. The value of magnetic field at the point P midway between the magnets is \(\alpha \times 10^{-3}\) T. The value of \(\alpha\) is ______.
(\(\mu_0=4\pi \times 10^{-7}\) Tm/A)
- A 10
- B 12
- C 14
- D 16
Answer & Solution
Correct Answer
(B) 12
Step-by-step Solution
Detailed explanation
Let the magnetic moment of each magnet be \(M = 3\sqrt{5}\) J/T. The distance of point P from the center of each magnet is \(r = 5\) cm \(= 0.05\) m. For the first magnet (horizontal), point P lies on its axial line. The magnetic field at P due to the first magnet is:…
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