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 fieldWe 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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