Presentation is loading. Please wait.

Presentation is loading. Please wait.

Do now! Can you read page 212 of your text book?.

Similar presentations


Presentation on theme: "Do now! Can you read page 212 of your text book?."— Presentation transcript:

1 Do now! Can you read page 212 of your text book?

2 Last lesson The motor effect and building a loudspeaker

3 The Motor Effect When a current is placed in a magnetic field it will experience a force (provided the current is not parallel to the field). This is called the motor effect. Can you copy this sentence into your books please.

4 The Motor Effect The direction of the force on a current in a magnetic field is given by Flemming’s left hand rule. Centre finger = Conventional Current First finger = Field direction Thumb = Motion

5 Building a loudspeaker These also use the motor effect Coil in here magnet

6 Homework Pages 210 to 213. Answer the questions on all pages. Finish for homework due 15 th October

7 Today’s lesson How the motor effect can build a motor Electromagnetic induction

8 Gather round!

9 D.C.Motor Commutator ensures that every half rotation the current direction reverses in the coil brushes

10 D.C.Motor

11 Electromagnetic induction Make a coil using wire. The coil should be wide enough to easily move a magnet inside

12 Electromagnetic induction Put your coil in this circuit. The multimeter should be on the μA scale. μAμA

13 Electromagnetic induction MOVE a magnet in and out of the coil. Watch the meter! μAμA

14 Electromagnetic induction If a magnet is moved inside a coil an electric current is induced (produced)

15 Electromagnetic induction If a magnet is moved inside a coil an electric current is induced (produced) COPY this please!

16 Electromagnetic induction A electric current is induced because the magnetic field around the coil is changing.

17 Gather round Again?

18 Generator/dynamo A generator works in this way by rotating a coil in a magnetic field (or rotating a magnet in a coil)

19 Motor = generator If electric energy enters a motor it is changed into kinetic energy, but if kinetic energy is inputted (the motor is turned) electric energy is produced!

20 Let’s try some questions! Pages 214 and 215.


Download ppt "Do now! Can you read page 212 of your text book?."

Similar presentations


Ads by Google