Question

Problem 27.64 At the equator, the direction of Earth's magnetic field is horizontal and to the north, and the magnitude is 3.5 ×10−5T.

Part A What is the magnetic flux through a circular loop of radius 0.30 m , lying flat on the ground at the equator? Φ Φ =   Wb   SubmitRequest Answer Part B What is the magnetic flux through the loop of radius 0.30 m balanced on its edge on the ground at the equator, when the axis that runs perpendicular to the plane of the loop points northwest? Φ Φ = nothing   Wb   SubmitRequest Answer Part C What is the magnetic flux through the loop of radius 0.30 m balanced on its edge on the ground at the equator, when the axis that runs perpendicular to the plane of the loop is points due north? Φ Φ = nothing   Wb   SubmitRequest Answer Part D What is the magnetic flux through the loop of radius 0.30 m balanced on its edge on the ground at the equator, when the axis that runs perpendicular to the plane of the loop is points to the west? Φ Φ = nothing   Wb

Answer 1

Area of the loop A= 0.3² = 0.28 n , n is perpendicular to the surface - area vector

earth magnetic field  B = 3.5e-5 T - North ward

flux = B . A

A . when the the loop is lying flat on the surface of earth B and A are perpendicular , the dot product =0

flux = BACos(90) =0

B. when the loop axis pointing NW angle between B and the area vector = 45 deg

= BA Cos(45) = 3.5e-5 * 0.28 * Cos(45) = 7.0e-6 wb

C. when the loop pointing North, angle between the vectors =0

= BA Cos(0) = 3.5e-5 * 0.28 Cos(0) = 9.8e-6 wb

D. When the loop is pointing WEST angle between the vector =90 deg

= BA Cos(90) = 0