Three long, straight, parallel conductors A, B and C are fixed in the same plane.…

PHYSICS · Multi-part · AP · Physics 2: Algebra-based · Magnetism and Electromagnetism · Magnetism and Electromagnetism

Problem

Three long, straight, parallel conductors A, B and C are fixed in the same plane. Conductors A and B are

4.0\,\text{cm}

apart. Conductor C lies on the same straight line, on the opposite side of B from A, at an unknown distance

x

from B. The currents are

I_A = 50\,\text{A}

(into the page),

I_B = 40\,\text{A}

(out of the page) and

I_C = 30\,\text{A}

(into the page). (i) Write expressions for the magnitudes and directions of the forces per unit length exerted on conductor B by conductors A and C. (ii) Imposing the condition that the net force per unit length on conductor B is zero, obtain an equation for

x

and hence calculate its value. (iii) For the separation found in part (ii), determine the magnitude and nature (attractive or repulsive) of the force per unit length between conductors A and C.

Related theory

Browse the problem library