Resistors by suchenfz

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									      Lesson 2
            Resistors
Resistor colour codes
           Capacitors
Resistors
   Provide resistance to the flow of electrons
       Limit the flow of current
       Imagine squeezing a hose pipe, the amount of
        water passing through the pipe will be less

   Can be rated by…
       Resistance - measured in Ohms (Ω)
       Tolerance (% of nominal value)
       Power Rating (Watts)

   Schematic Symbol…
Resistors – Types

 Fixed




   Variable (Potentiometer, Rheostat)
Resistors

Use the colours to work out
the value of the resistor     0 - black
                              1 - brown
                              2 - red
                              3 - orange
                              4 - yellow
                              5 - green
                              6 - blue
                              7 - purple
                              8 - grey
                              9 - white

                              gold - 5%
                              silver – 10%
                                                     0 - black
                                                     1 - brown
Resistors - Example 1                                2 - red
                                                     3 - orange
                                                     4 - yellow
                                                     5 - green
                                                     6 - blue
                                                     7 - purple
                                                     8 - grey
                                                     9 - white

                                                     gold - 5%
                                                     silver – 10%
       First number         Tolerance
           2
                                        5%


           6
       Second number   Number of 0’s     Resistance = 260Ω
                          1 zero
Resistors – Example 2
First number                Tolerance
       3                                                   0 - black
                                        5%
                                                           1 - brown
                                                           2 - red
                                                           3 - orange
       3
                                                           4 - yellow
Second number          Number of 0’s
                                                           5 - green
                        2 zeros
                                                           6 - blue
                                                           7 - purple
                                                           8 - grey
          1st band: orange = 3                         9 - white

          2nd band: orange = 3                         gold - 5%
                                                        silver – 10%
          3rd band: red = 2 zeros
          4th band: gold = 5%     Resistance = 3300Ω or 3.3 kΩ
More Examples                           0 - black
                                        1 - brown
                                        2 - red
                            470000 Ω
                                        3 - orange
                            470K Ω      4 - yellow
                            1000 Ω      5 - green
                            1K Ω        6 - blue
                                        7 - purple
                            56 Ω        8 - grey
                                        9 - white
                            1500 Ω
                                        gold - 5%
                            1.5K Ω
                            33000 Ω     silver – 10%

                            33K Ω
                            6400000 Ω
                            6.4M Ω



    1000 Ω = 1KΩ
    1000000 Ω = 1000K Ω =1M Ω
Resistors – 5 Band Colour Code
Resistors – Typical Power
Ratings
Capacitors
    Stores electric charge
    Two metal plates separated by an
     insulator
    Different Designs
Capacitors
    Measured in Farads (F) but
     generally not this large, usually:
    Micro Farad (µF) or pico farads (pf)


    Schematic Symbol….

                          or
Capacitors
    Slowly charges up until the voltage
     is the same as the battery
    Can store the charge for a long time
     or until a conductor is connected
     across it
    Several uses
        AC to DC converter
        Timing circuits
        Radio receivers
Common Capacitor Types



                                                  Surface mount

                            Disc
 Electrolytic – polarized




                                   High Voltage
Questions:
     Use the colour code chart to complete these:
1st Number   2nd Number        3rd Number   4th Number   Resistor Value

Red          Blue              Orange       Silver

Green        Black             Brown        Gold

Yellow       Violet / Purple   Black        Gold

White        Gray              Red          Silver

Orange       Orange            Yellow       Gold

                                                         360 Ω ±5%

                                                         10 Ω ± 10%

                                                         4700 Ω ± 5%

                                                         5 Ω ± 10%

                                                         8000 Ω ± 5%

                                                         33000000 Ω ± 5%

								
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