Write the formula for the magnetic field at a point on the axis of a circular current-carrying loop of radius $R$ at a distance $x$ from its center,where $x >> R$.

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(N/A) The magnetic field $B$ on the axis of a circular loop of radius $R$ carrying current $I$ at a distance $x$ from the center is given by the formula:
$B = \frac{\mu_0 I R^2}{2(x^2 + R^2)^{3/2}}$
Given the condition $x >> R$,we can neglect $R^2$ in the denominator compared to $x^2$:
$B \approx \frac{\mu_0 I R^2}{2(x^2)^{3/2}}$
$B \approx \frac{\mu_0 I R^2}{2x^3}$
Multiplying the numerator and denominator by $\pi$:
$B \approx \frac{\mu_0 I (\pi R^2)}{2\pi x^3}$
Since the magnetic dipole moment $m = I A = I(\pi R^2)$,the formula becomes:
$B \approx \frac{\mu_0 m}{2\pi x^3}$

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