1. Controls, Switches and Energy Transformation

2. CONTROL
The function performed by a component that can open or close a circuit
switches and pushbuttons are examples of controls

3. SWITCHES SINGLE POLE SWITCH OPENS/CLOSES 1 CONTACT AT A TIME
DOUBLE POLE CAN OPEN/CLOSE TWO CONTACTS AT ONCE
ELECTRONS FOLLOW 1 PATH IN SINGLE THROW SWITCH
DOUBLE THROW ALLOWS ELECTRONS TO FOLLOW 1 OF 2 PATHS
P470

4. SWITCHES
A switch is deemed to be closed when a connection is made. If you have a closed switch you will then have a closed circuit.
Open Closed

5. Switches Switch Number of contacts that are open
Number of possible paths for electrons
Diagram
Single Pole Single Throw 1
Single – Pole Double – Throw 2
Double – Pole Single – Throw
Double – Pole Double – Throw

6. SWITCHES
ROCKER
SWITCH

7. TOGGLE SWITCH

8. PUSH BUTTON

9. MAGNETIC CONTACT

10. ENERGY TRANSFORMATION
CHANGE OF ONE FORM OF ENERGY TO ANOTHER FORM OF ENERGY

11. EXAMPLES OF ELECTRICAL COMPONENTS USED TO TRANSFORM ELECTRICITY
INCANDESCENT BULBS- NEW FORM-LUMINOUS ENERGY

12. HEATING ELEMENT- NEW FORM- THERMAL ENERGY

13. PIEZOELECTRIC CRYSTALS- NEW FORM – MECHANICAL OR SOUND ENERGY

14. ELECTROMAGNETS – NEW FORM OF ENERGY – MAGNETIC ENERGY

15. COMPONENTS WITH OTHER FUNCTIONS
CAPACITORS
DIODES
TRANSISTORS (AST ONLY)
RELAYS (AST ONLY)

16. CAPACITORS CAN STORE ELECTRICAL CHARGE
COMPOSED OF TWO ELECTRICAL SURFACES SEPARATED BY AN INSULATOR (BLOCKS THE FLOW OF ELECTRONS)
CHARGE BUILDS UP ON ONE PLATE, INSULATOR IS REMOVED AND CHARGE IS RELEASED ALMOST INSTANTLY

17. CAPACITORS The left part of the plate attracts all the electrons.
Dielectric
The left part of the plate attracts all the electrons.
The right side of the plate is positively charged as the power supply attracts all the electrons.
This plate stops the flow of electrons, but at the same time the capacitor stores a charge.
Once the capacitor is pushed out of the way and electricity can flow, you will have a strong charge that will happen in a short period of time.
Plate - + - + - + - - + - + - + - +

18. CAPACITOR CHARGE FROM CAMERA BATTERY BUILDS UP UNTIL BUTTON IS PRESSED
FULL CHARGE
IS RELEASED IN
THE FLASH

19. DIODE ALLOWS ELECTRIC CURRENT TO FLOW IN ONE DIRECTION
MADE OF SEMICONDUCTOR
PROTECTS ELECTRONIC PARTS FROM HAVING ELECTRONS FLOW IN THE WRONG DIRECTION – NOTABLY WHEN A BATTERY (IS INCERTED IN THE WRONG WAY) OR POWER SUPPLY IS PUSHING ELECTRONS THE WRONG DIRECTION

20. DIODE USED TO CONVERT AC TO DC
LED’S ARE ‘LIGHT EMITTING DIODES’ THAT GIVE OFF LIGHT WHEN CURRENT FLOWS THROUGH THEM

21. TRANSISTORS (AST ONLY)
BLOCK OR AMPLIFY AN ELECTRIC CURRENT

22. TRANSISTORS (AST ONLY)
CURRENT FLOWS FROM COLLECTOR TO EMITTER TO BASE
BASE ACTS LIKE A VALVE THAT ALLOWS CURRENT TO FLOW FREELY; BLOCK FLOW OR ALLOW SOMEWHERE IN BETWEEN
CONNECTION BETWEEN TRANSISTORS AND COMPUTERS P477 OF OBSERVATORY

23. RELAYS (AST ONLY)
A RELAY OPENS OR CLOSES A CIRCUIT USING AN ELECTRICAL SIGNAL FROM ANOTHER CIRCUIT (THINK RELAY RACE-PASSING ON)

24. RELAYS (AST ONLY)
COMMONLY USED TO CONTROL HIGH VOLTAGE CIRCUITS FROM A REMOTE DISTANCE, HEATING SYSTEMS,
LIGHTING IN A THEATRE, HIGH VOLTAGE APPLIANCES (X-RAY MACHINE)