Section 16.5 Simple D.c. Motor Section 16.5 Simple D.c. Motor

Section 16.5 Simple d.c. motor

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16.5 Simple d.c. motor (SB p. 124)

Simple d.c. motor Motors found in many electrical appliances

Go to

Discussion 6 © Manhattan Press (H.K.) Ltd.

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16.5 Simple d.c. motor (SB p. 125)

Simple d.c. motor Expt. 16E Model electric motor magnet

armature

thin rod

to d.c. power supply © Manhattan Press (H.K.) Ltd.

split pin

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16.5 Simple d.c. motor (SB p. 126)

Simple d.c. motor Typical d.c. motor consists of permanent magnet armature rotation

CAL Workshop 2 Rotation of motor

commutator carbon brushes

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16.5 Simple d.c. motor (SB p. 127)

Simple d.c. motor plane of coil // field lines

rotates in clockwise © Manhattan Press (H.K.) Ltd.

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16.5 Simple d.c. motor (SB p. 127)

Simple d.c. motor plane of coil ⊥ field lines by inertia

circuit broken © Manhattan Press (H.K.) Ltd.

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16.5 Simple d.c. motor (SB p. 127)

Simple d.c. motor plane of coil // field lines again

rotates in clockwise © Manhattan Press (H.K.) Ltd.

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16.5 Simple d.c. motor (SB p. 127)

Simple d.c. motor plane of coil ⊥ field lines again

circuit broken © Manhattan Press (H.K.) Ltd.

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16.5 Simple d.c. motor (SB p. 128)

Simple d.c. motor Turning effect depends on (1) magnitude of I (2) no. of turns of wire (3) strength of magnet (4) area of coil © Manhattan Press (H.K.) Ltd.

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16.5 Simple d.c. motor (SB p. 132)

Useful Website

科學小豆芽 (http://www.bud.org.tw/Ma/Ma19.htm) NASA'S Image Reveals Earth's Invisible Magnetic Tail (http://www .gsfc.nasa.gov/gsfc/spacesci/sunearth/imagescie ) Simple Electric Motors (http://www.simplemotor.com) © Manhattan Press (H.K.) Ltd.

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16.5 Simple d.c. motor (SB p. 132)

Mind Map

magnet

S and N poles

16.1 Magnetic force and magnetic field

around a magnet

magnetic field

Magnetic effect of a current

represented by due to

magnetic effect

3 currentcarrying conductors

moving charges / electric current

magnetic field patterns are governed by right-hand grip rule

circular coil solenoid

16.3 Electromagnet

application direction is governed by

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magnetic field line

straight wire

16.2 Magnetic effect of electric current

16.4 Force on currentcarrying conductor in magnetic field

unlike poles attract; like poles repel

turning effect on a coil

Fleming’s left-hand rule

application

16.5 Simple d.c. motor 11

The End

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16.5 Simple d.c. motor (SB p. 124)

Discussion 6:

List some applications of electric motor in our Ans daily lives. wer

Vacuum cleaner, can opener, microwave oven, fan, juicer and water sprayer. Return to

Text

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