Consider the following figure. -l- i μπ (a) A conducting loop in the shape of a square of edge length l = 0.420 m carries a current I figure above. Calculate the magnitude and direction of the magnetic field at the center of the square. magnitude = 8.80 A as in the direction ---Select--- (b) If this conductor is reshaped to form a circular loop and carries the same current, what is the value of the magnetic field at the center? magnitude direction μπ ---Select---

When the current through a circular loop is 6.0 A, the magnetic field at its center is 2.0104 T. What is the radius of the loop?

A long, straight wire of radius R caries a current I that is distributed uniformly over the cross-section of the wire. At what distance from the axis of the wire is the magnitude of the magnetic field a maximum?

A circular loop of radius R carries a current I. At what distance along the axis of the loop is the magnetic field one- half its value at the center of the loop?

Two long, parallel wires carry currents of 20.0 A and 10.0 A in opposite directions (Fig. OQ22.13). Which of the following statements is true? More than one statement may be correct. (a) In region I, the magnetic field is into the page and is never zero. (b) In region II, the field is into the page and can be zero. (c) In region III, it is possible for the field to be zero. (d) In region I, the magnetic field is out of the page and is never zero. (e) There are no points where the field is zero. Figure OQ22.13 Objective Questions 13 and 14.

A 5.0-m section of a long, straight wire carries a current of 10 A while in a uniform magnetic field of magnitude 8.0103T . Calculate the magnitude of the force on the section if the angle between the field and the direction of the current is (a) 45°; (b) 90°; (C) 0°; or (d) 180°.

A flat, circular loop has 20 turns. The radius of the loop is 10.0 cm and the current through the wire is 0.50 A. Determine the magnitude of the magnetic field at the center of the loop.

A nonconducting hard rubber circular disk of radius R is painted with a uniform surface charge density tr. It is rotated about its axis with angular speed . (a) Find the magnetic field produced at a point on the axis a distance h meters from the center of the disk, (b) Find the numerical value of magnitude of the magnetic field when =1C/m2 , R = 20 cm, h = 2 cm, and magnetic field of Earth, which is about 1/2 Gauss. =400rad/sec , and compare it with the magnitude of

A wire ismade into a circular shape of radius R and pivoted along a central support.The two ends of the sire are touching a banish that is connected to a &power source. The stricture is between the poles of a magnet such that we can assume there is a uniform magnetic field on the wire. In terms of a coordinate system with origin at the center ofthe ring, magneticfieldisBx=B0,By=Bz= 0. and the ring rotates about the z-axis. Find the torque on the ring siren it is not in the xz-plane.

Magnetic Field Due to a Long, Straight Wire In a laboratory, you measure the magnitude of the magnetic field generated by a long, straight wire, and you plot your resultsB as a function of position r. Which of the graphs in Figure 31.15 best represents the magnetic field due to a long, straight wire?