Question
Physics Question on Moving charges and magnetism
A current loop, having two circular arcs joined by two radial lines is shown in the figure. It carries a current of 10A. The magnetic field at point O will be close to :
A
1.0×10−5T
B
1.5×10−5T
C
1.0×10−7T
D
1.5×10−7T
Answer
1.0×10−5T
Explanation
Solution
B=4πμ0iθ[r11−r21]k^
r1=3cm=3×10−2m
r2=5cm=5×10−2m
θ=4π,i=10A
⇒B=164π×10−7×10[3×10−21−5×10−21]k^
⇒B=3π×10−5T
≈1×10−5T