(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Determine the B field at a point P with distance d from centre of current ring radius r (d>r ie outside ring of current) but IN the Plane of ring (i.e off the axis)

2. Relevant equations

Biot savart: db=(u.I/4pi.r^2).dl.sinx

u=mu, I=current, x=angle made with current vector element dl and vector r connecting P to dl.

3. The attempt at a solution

the angle x will vary at all points along ring with vector joining point P, as will r.

I will integrate from 0 to 2pi my expression for db but with r^2=a^2+d^2-2adcosy

where y is angle between radial vector and d.

I am stuck because cannot determine how to express y in terms of x. and thus cannot integrate!

many thanks!

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# Homework Help: Finding the B-field at a point outside ring of current IN Plane of ring

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