A single, very long (effectively infinite) wire comes in and is bent around poin
ID: 1415634 • Letter: A
Question
A single, very long (effectively infinite) wire comes in and is bent around point P in the shape shown in the Figure (all in one plane) where the outer circular segments have radius 24.0 cm, concentric with point P. and the inner loop having radius 12 cm, is also concentric with point P. The separation between the parallel segments of the wire is exaggerated for clarity (they he virtually on top of each other, in line with point P, while being electrically isolated). A current of 4.50 A flows in the direction indicated by the arrows. With the positive direction lying out of the page, the net magnetic field at point P (in muT) is? -11.8 +11.8 -1.88 +1.88 -6.33 3 5 4 1 2Explanation / Answer
outer radius b=24 cm
inner radius a=12 cm
current i=4.5 A
this concept belongs to moving charges and magnetic field
the magnetic field B=4*pi*N*10^-7*i log(b/a)/2[b-a]
=2*3.14*10^-7*4.5*log(24/12)/[b-a]
=1*10^-6
the correct option is D