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Magnetism And Matter — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsMagnetism And Matter3 Marks
Question
Three identical bar magnets are rivetted together at centre in the same plane as shown in Fig. This system is placed at rest in a slowly varying magnetic field. It is found that the system of magnets does not show any motion. The north-south poles of one magnet is shown in the Fig. Determine the poles of the remaining two.

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Answer

When the net force on the system is zero and net torque on the system is also zero then the system is in stable equilibrium. This is possible only when the poles of the remaining two magnets are as shown in the figure given below.

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