Suppose that the dipole moment associated with an iron atom of an iron bar is 2.8 × 10 23 J/T. The bar is 5.2 cm long and has a cross-sectional area of 1.5 cm². Two-thirds of the atoms have their dipole moment in one directions and remaining one-third have their dipole moment in the opposite direction. What torque (in N*m) must be exerted to hold this magnet perpendicular to an external field of 1.2 T? (The density of iron is 7.9 g/cm3 and its molar mass is 55.9 g/mol. Avogadro's number is 6.022*1023 atoms/mol.)

Suppose that the dipole moment associated with an iron atom of an iron bar is 2.8 × 10 23 J/T. The bar is 5.2 cm long and has a cross-sectional area of 1.5 cm². Two-thirds of the atoms have their dipole moment in one directions and remaining one-third have their dipole moment in the opposite direction. What torque (in Nm) must be exerted to hold this magnet perpendicular to an external field of 1.2 T? (The density of iron is 7.9 g/cm3 and its molar mass is 55.9 g/mol. Avogadro's number is 6.0221023 atoms/mol.)

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

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