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Chapter 28. Sources of Magnetic Field (cont.). Q28.5. The long, straight wire AB carries a 14.0-A current as shown. The rectangular loop has long edges parallel to AB and carries a clockwise 5.00-A current.
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Chapter 28 Sources of Magnetic Field (cont.)
Q28.5 The long, straight wire AB carries a 14.0-A current as shown. The rectangular loop has long edges parallel to AB and carries a clockwise 5.00-A current. What is the direction of the net magnetic force that the straight wire AB exerts on the loop? to the right to the left C. upward (toward AB) D. downward (away from AB) E. The net magnetic force is zero
A28.5 The long, straight wire AB carries a 14.0-A current as shown. The rectangular loop has long edges parallel to AB and carries a clockwise 5.00-A current. What is the direction of the net magnetic force that the straight wire AB exerts on the loop? to the right to the left C. upward (toward AB) D. downward (away from AB) E. The net magnetic force is zero
Q28.6 A wire consists of two straight sections with a semicircular section between them. If current flows in the wire as shown, what is the direction of the magnetic field at P due to the current? to the right to the left C. out of the plane of the figure D. into the plane of the figure E. misleading question—the magnetic field at P is zero
A28.6 A wire consists of two straight sections with a semicircular section between them. If current flows in the wire as shown, what is the direction of the magnetic field at P due to the current? to the right to the left C. out of the plane of the figure D. into the plane of the figure E. misleading question—the magnetic field at P is zero
Q28.7 The wire shown here is infinitely long and has a 90° bend. If current flows in the wire as shown, what is the direction of the magnetic field at P due to the current? to the right to the left C. out of the plane of the figure D. into the plane of the figure E. none of these
A28.7 The wire shown here is infinitely long and has a 90° bend. If current flows in the wire as shown, what is the direction of the magnetic field at P due to the current? to the right to the left C. out of the plane of the figure D. into the plane of the figure E. none of these
Q28.8 The figure shows, in cross section, three conductors that carry currents perpendicular to the plane of the figure. If the currents I1, I2, and I3 all have the same magnitude, for which path(s) is the line integral of the magnetic field equal to zero? path a only paths a and c paths b and d paths a, b, c, and d The answer depends on whether the integral goes clockwise or counterclockwise around the path.
A28.8 The figure shows, in cross section, three conductors that carry currents perpendicular to the plane of the figure. If the currents I1, I2, and I3 all have the same magnitude, for which path(s) is the line integral of the magnetic field equal to zero? path a only paths a and c paths b and d paths a, b, c, and d The answer depends on whether the integral goes clockwise or counterclockwise around the path.
Chapter 29 Electromagnetic Induction
A changing magnetic flux causes an induced current. See Figure 29.1 below. • The induced emf is the corresponding emf causing the current. Induced current
Figure 29.3 below shows how to calculate the magnetic flux through an element of area. Magnetic flux through an area element
Follow the text discussion on the direction of the induced emf, using Figure 29.6 below. Direction of the induced emf
Q29.1 A circular loop of wire is in a region of spatially uniform magnetic field. The magnetic field is directed into the plane of the figure. If the magnetic field magnitude is constant, A. the induced emf is clockwise. B. the induced emf is counterclockwise. C. the induced emf is zero. D. The answer depends on the strength of the field.
A29.1 A circular loop of wire is in a region of spatially uniform magnetic field. The magnetic field is directed into the plane of the figure. If the magnetic field magnitude is constant, A. the induced emf is clockwise. B. the induced emf is counterclockwise. C. the induced emf is zero. D. The answer depends on the strength of the field.