Answer
given,
current (I) = 16 mA
circumference of the circular loop (S)= 1.90 m
Magnetic field (B)= 0.790 T
S = 2 π r
1.9 = 2 π r
r = 0.3024 m
a) magnetic moment of loop
M= I A
M=[tex]16 \times 10^{-3} \times \pi \times r^2[/tex]
M=[tex]16 \times 10^{-3} \times \pi \times 0.3024^2[/tex]
M=[tex]4.59 \times 10^{-3}\ A m^2[/tex]
b) torque exerted in the loop
[tex]\tau = M\ B[/tex]
[tex]\tau = 4.59 \times 10^{-3}\times 0.79[/tex]
[tex]\tau = 3.63 \times 10^{-3} N.m[/tex]
