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neel g
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Doesn't F=ILB violate the conservation of energy?

Assume we have a current carrying conductor of finite-length $l$, carrying a current of $I$ (w/ a negligible cross-sectional area) under the influence of a Magnetic field, whose constant Flux density is $B$ (units ignored) All under a vacuum. Now, we know the famous equation, $$ F = ILB $$ Where a conductor suffers a Force in the orthogonal direction to the Magnetic field.

Suppose now, we increase the length of this conductor, $l' = kl \, \text{where}\, k\in R^+$.

Thus, by our equation above, we will get $k$ times more Force than before.

Now, I'm well aware that $\text{Force}\neq\text{Energy}$, But $W=Fs$ where $s\rightarrow \text{displacement}$ and as I said, the entire system is in a vacuum. Therefore, after extending my conductor by $k$, We get:

$$ W' = (kF).s = kW $$

So just by extending the conductor, I've obtained new, $k$ times more energy in the system. This conductor had negligible resistance (But $\neq 0$) so the loss of the current $I$ throughout the conductor would be negligible. $B$ is fixed. Nothing has changed except $l' = kl$, which shouldn't introduce new energy in the system at all (After all, we're just introducing free electrons to carry the current - like adding more pans in a conveyor belt waiting to be filled with sauce).

This would violate the conservation of energy, so I'm obviously wrong. But where?

neel g
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