AP EAMCET202419 May 2024Evening ShiftPhysicsMagnetic Properties of MatterActual
The domain in ferromagnetic material is in the form of a cube of side 2 ~m . Number of atoms in that domain is 9 10¹⁰ and each atom has a dipole movement of 9 10⁻²⁴ Am ^2 . The magnetisation of the domain is (approximately),
Options
- A10 10^4 Am ⁻¹
- B8 10^4 Am ⁻¹
- C12 10^4 Am ⁻¹
- D9 10^4 Am ⁻¹
Correct answer
A. 10 10^4 Am ⁻¹
Step-by-step solution
Volume of the domain, V = (2 10⁻⁶ )^3=8 10⁻¹⁸ ~m ^3 aligned & M_ net =9 10¹⁰ 9 10⁻²⁴=81 10⁻¹⁴ Am ^2 & Magnetisation, I= M_ net V = 81 10⁻¹⁴ 8 10⁻¹⁸ & =10 10^4 ~A m ⁻¹ aligned