A Wire in the Shape of an "M" Lies in the Plane

question 146

Multiple Choice

A wire in the shape of an "M" lies in the plane of the paper. It carries a current of $2.0 \mathrm {~A}$ , flowing from $A$ to $E$ , as shown in the figure. It is placed in a uniform magnetic field of $0.85 \mathrm {~T}$ in the same plane, directed as shown on the right side of the figure. The figure indicates the dimensions of the wire. Note that $A B$ is parallel to $D E$ and to the baseline from which the magnetic field direction is measured. What are the magnitude and direction of the force acting on section DE of this wire?

• A) \(0.30 \mathrm {~N}\) perpendicular out of the page
• B) \(0.30 \mathrm {~N}\) perpendicular into the page
• C) \(0.20 \mathrm {~N}\) perpendicular out of the page
• D) \(0.12 \mathrm {~N}\) perpendicular into the page
• E) \(0.12 \mathrm {~N}\) perpendicular out of the page

---

Definitions:

Governor Cut-Out Pressures

The maximum pressure at which the compressor governor stops the compressor from pumping air into an air brake system.

Compliant

Meeting or in accordance with established guidelines, regulations, or standards.

Relay Valve Crack Pressures

The initial pressure at which a relay valve starts to open or change its state in a compressed air system, important for the timing and control of air flow.

Service Brakes

The primary braking system used during normal vehicle operation, enabling a driver to reduce speed or bring the vehicle to a stop.