Answer:
A) τmax = 3.59×10^-3 Nm
B) a. the plane of the ring should be parallel to the field
Explanation:
A) the torque exerted by an external magnetic field is given by:
τ = μ×Bext
where μ is perpendicular to the plane of the current loop and has magnitude IA. I is the current in the loop and A is the loop's area.
A circular current loop with radius R has a magnetic field at its center given by B = μ0I/(2R)
I = 2RB/μ0
= [2(0.0290)(77.6×10-6)]/(4π×10^-7)
= 3.58A
τ = μ×Bextsin(Ф)
= IA×Bextsin(Ф)
where Ф is the angle between μ and Bext. the maximum magnitude will occur when sinФ = 1 , Ф = 90°. then:
τmax = Iπ(R^2)Bext
= (3.58)π((0.029)^2)(0.38)
= 3.59×10^-3 Nm
b) in order for the ring to experience the maximum torque, the magnetic moment of the loop, μ , and the external magnetic field , Bext, must be perpendicular to each other .
a. the plane of the ring should be parallel to the field
