Question

Shown in the figure is a conductor carrying a current I. The magnetic field intensity at the point O(common centre of all the three arcs) is:

• A.
• B. $\frac { \mu _ { 0 } \mathrm { I } \theta } { 24 \pi \mathrm { r } }$
• C. $\frac { 11 \mu _ { 0 } \mathrm { I } \theta } { 24 \pi \mathrm { r } }$
• D. Zero

Answer 1

Answer: (A)

Answer 2

Hint : Find B due to each arc at O and add them using vector addition. Since magnetic field at the centre of an arc is equal to B = q hence, net B = q = $\frac { 5 \mu _ { 0 } \mathrm { I } \theta } { 24 \pi \mathrm { r } }$