CourseNotes.36

# CourseNotes.36 - Using this direction for the magnetic...

This preview shows page 1. Sign up to view the full content.

This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Using this direction for the magnetic moment, we can write down the torque on a magnetic dipole ~ τ = ~μ × ~ B (32) We can also define a magnetic potential energy associated with the direction of the dipole in the field. U ( θ ) =- ~μ · ~ B 9.6 Problems Problem 27.44 In figure 29, a metal wire of mass m = 24 . 1 mg can slide with negligible friction on two horizontal parallel rails separated by distance d = 2 . 56 cm . The track lies in a vertical uniform magnetic field of magnitude 56 . 3 mT . At time t = 0, device G is connected to the rails, producing a constant current i = 9 . 13 mA in the wire and rails (even as the wire moves). At t = 61 . 1 ms , what are the wire’s (a) speed and (b) direction of motion (left or right)? Figure 29: Figure for Problem 27.44. Part (b) is easy enough to do that we might as well do it first. The direction of the force on the sliding piece of wire is given by the right hand rule. If we lay our hands along the direction of the current and curl our fingers into the direction of the magnetic field, our thumb is left pointing...
View Full Document

## This note was uploaded on 12/05/2011 for the course PHY 2049 taught by Professor Any during the Spring '08 term at University of Florida.

Ask a homework question - tutors are online