Copyright © 2007, Pearson Education, Inc., Publishing as Pearson Addison-Wesley. Magnets and the magnetic field Electric currents create magnetic fields Magnetic fields of wires, loops, and solenoids Magnetic forces on charges and currents Magnets and magnetic materials Chapter 24 Magnetic Fields and Forces Topics: Sample question: This image of a patient’s knee was made with magnetic fields, not x rays. How can we use magnetic fields to visualize the inside of the body? Slide 24-1
Drawing Field Vectors and Field Lines of a Current-Carrying Wire Slide 24-21
Copyright © 2007, Pearson Education, Inc., Publishing as Pearson Addison-Wesley. Drawing a Current Loop Slide 24-22
Copyright © 2007, Pearson Education, Inc., Publishing as Pearson Addison-Wesley. The Magnetic Field of a Current Loop Slide 24-23
Copyright © 2007, Pearson Education, Inc., Publishing as Pearson Addison-Wesley. The Magnetic Field of a Solenoid A short solenoidA long solenoid Slide 24-24
Copyright © 2007, Pearson Education, Inc., Publishing as Pearson Addison-Wesley. The Magnitude of the Field due to a Long, Straight, Current-Carrying Wire Slide 24-25
Copyright © 2007, Pearson Education, Inc., Publishing as Pearson Addison-Wesley. Slide 24-26
Copyright © 2007, Pearson Education, Inc., Publishing as Pearson Addison-Wesley. Checking Understanding A.10 A to the right. B.5 A to the right. C.2.5 A to the right. D.10 A to the left. E.5 A to the left. F.2.5 A to the left. The magnetic field at point P is zero. What are the magnitude and direction of the current in the lower wire? Slide 24-27
Copyright © 2007, Pearson Education, Inc., Publishing as Pearson Addison-Wesley. E.5 A to the left. The magnetic field at point P is zero. What are the magnitude and direction of the current in the lower wire? Slide Answer
Copyright © 2007, Pearson Education, Inc., Publishing as Pearson Addison-Wesley. The Magnetic Field of a Current Loop Magnetic field at the center of a current loop of radius R Magnetic field at the center of a current loop with N turns Slide 24-29
Copyright © 2007, Pearson Education, Inc., Publishing as Pearson Addison-Wesley. Example What is the direction and magnitude of the magnetic field at point P, at the center of the loop? Slide 24-30
Copyright © 2007, Pearson Education, Inc., Publishing as Pearson Addison-Wesley. The Magnetic Field Inside a Solenoid Magnetic field inside a solenoid of length L with N turns. Slide 24-31
Copyright © 2007, Pearson Education, Inc., Publishing as Pearson Addison-Wesley. The Force on a Charged Particle Moving in a Magnetic Field Slide 24-32
Copyright © 2007, Pearson Education, Inc., Publishing as Pearson Addison-Wesley. The Right-Hand Rule for Forces Slide 24-33
Copyright © 2007, Pearson Education, Inc., Publishing as Pearson Addison-Wesley. Slide 24-34
Copyright © 2007, Pearson Education, Inc., Publishing as Pearson Addison-Wesley. Paths of Charged Particles in Magnetic Fields Slide 24-35
Copyright © 2007, Pearson Education, Inc., Publishing as Pearson Addison-Wesley. Magnetic Fields Exert Forces on Currents Magnitude of the force on a current segment of length L perpendicular to a magnetic field Slide 24-37