A long, straight wire lies on a horizontal table in the

Chapter 19, Problem 19.85

(choose chapter or problem)

A long, straight wire lies on a horizontal table in the xy-plane and carries a current of 1.20 mA in the positive x-direction along the x-axis. A proton is traveling in the negative x- direction at speed 2.30 _ 104 m/s a distance d above the wire (i.e. z _ d). (a) What is the direction of the magnetic fi eld of the wire at the position of the proton? (b) What is the direction of the magnetic force acting on the proton? (c) Explain why the direction of the protons motion doesnt change. (d) Using Newtons second law, fi nd a symbolic expression for d in terms of the acceleration of gravity g, the proton mass m, its speed v, charge q, and the current I. (e) Find the numeric answer for the distance d using the results of part (d).