Post on 20-Jan-2016
transcript
Ch. 22 - Magnetism
Ch. 22 - Magnetism
II. Uses of Magnetic Fields
(p.628-632) Electromagnet Speaker Motor
A. ElectromagnetElectromagnet
strong, temporary magnet formed when current is passed through a coil of wire surrounding an iron core
acts like a bar magnet when current is on
B. SpeakerSpeaker
electrical energy mechanical energy
wire coil moves back & forth as its magnetic field interacts with the field of a fixed magnet
forced vibration causes the cone to move sound
C. MotorMotor
electrical energy mechanical energy
electromagnet rotates between the poles of a fixed magnet
commutator reverses the poles of the e’magnet
C. Motor
brushes & wires to battery field magnet
armature & commutatorassembled motor