Question

BRAINLY USERS....
Solve it .....

Answer 1

By Biot savart's law

dB = uidLsinα/4πR^2  [here α=90° because the tangent is always perpendicular to the perimetre ]

After integration....

B = (ui/4πR²)∫dL

The integration of dL will give us the length of the part Of bigger circular part of the circle.

That is  radius × angle

=R(2π-α)

So

B =(ui/4πR²){R(2π-α)}$B=\frac{u_{0} i}{4\pi R^{2}  } R(2\pi- \alpha )$

B = ui(2π-α)/4πR

$B = \frac{u_0I2 }{4R(\pi )} (\pi- \alpha/2)</p><p>B = \frac{u_0i}{2R} (1-\alpha /2\pi )</p><p>B=\frac{u_0i}{2R} (\frac{2\pi-\alpha }{2\pi } )$

This is the simple formula for calculating B  at center of circle when angle is given:-

B=uiα/4πR

Answer 2

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