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Moving Charges and Magnetism — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsMoving Charges and Magnetism3 Marks
Question
Prove that the force acting on a current-carrying wire, joining two fixed points a and b in a uniform magnetic field, is independent of the shape of the wire.
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Answer


For force on a current carrying wire in an uniform magnetic field

We need, l → length of wire

i → Current

B → Magnitude of magnetic field

Since $\overrightarrow{\text{F}}=\text{i}\ell\text{B}$

Now, since the length of the wire is fixed from A to B, so force is independent of the shape of the wire.

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