RESIST ME NOT

1
Introduction

• RESIST ME NOT
• SO THAT
• YOU WILL NOT BECOME ASH!
• Resistors are materials that impede the
  flow of current. Resistors are added in a circuit
  to provide measured resistance and regulate the
  flow of current to a specific value or to provide
  a desired voltage drop. These resistances are
  often a hundred, a thousand, or a million larger
  than those of connecting wires. Many
  manufacturers produce a wide range of fixed
  resistors which may be wirewound, tape metal
  film, cerment or carbon element. Some resistors
  consist of spools of fine, high-resistance wires
  covered with ceramics.

2
How do you use this module?

• Inspect the pages of this module and see if there
  are missing pages.
• Read and understand the lesson well.
• Do not skip any page of this module. Read
  everything from the first page up to the last.
• Perform all the given activities and exercises,
  answer them honestly and accurately.
• Enjoy working on it.

3
Pre-test

• I. Multiple choice
• Direction Analyze each statement or phrase
  and write the letter of your choice on the space
  provided before the number.
• __1. A type of non-linear resistor that is also
  known as light-dependent resistor(LDR) is
• A. photothermistor B. thermistor C. VDR
• ___2. The circuit symbol for thermistor is
• A.
  B. C.
• ____3. Another name for voltage-dependent
  resistor is
• A. metrosil. B.
  photocell C. thermistor.
• ___4. An electronic component that impede the
  flow of current is
• A. capacitor.
  B. diode C.
  resistor
• ___5. The degree to which a resistor is
  permitted to vary from its value is
• A. tolerance
  B. reliability C.
  resistivity
• ___6. A type of thermistor with many shapes and
  sizes from beads to larger rods or discs is a

4
Pre-test

• ____7. The measurement of the expected failure
  rate of the resistors per each one thousand
  hours of use is the
• A. tolerance. B. reliability. C. resistivity.
• ____8. A resistor with color bands red, brown,
  red, gold has a value of
• ______ ohms.
• A. 2 100 5
• B. 2 200 5
• C. 2 300 5
• ____9. Decode the bands of the resistor with a
  value of 320 10 ohms.
• A. red, red, brown, silver
• B. red, brown, orange, silver
• C. orange, red, brown, silver
• _____10. resistance is measured in
• A. ampere. B. ohm. C. volt
• II. MATCHING TYPE
• Directions Match column A to column B. Write
  the letter of your choice on the space provided
  before the number.
• COLUMN A COLUMN B
• (color of the bands in a resistor)
  (numerical value of the band)

5
Modular Program

• Lesson 1.
• What are the words associated with resistors?
• Do you know that there are two main categories
  of resistors?
• Learn more as you do the activity on the next
  page.

6
Activity 1- FIT MESpatial Ability

• Directions Fit the following words to the box
  provided at the next page.
• Time Allotment 5 minutes

3-letter 4-letter 5-letter 6-letter 8-letter 9-letter 10-letter
RED BLUE BLACK ORANGE RESISTOR CAPACITOR TRANSISTOR
OHM GRAY BROWN YELLOW TOLERANCE
LDR GOLD GREEN VIOLET
TDR WHITE SILVER
DIODE
7
Answer Sheet ACTIVITY 1- FIT ME!

















8
Lesson 2Two Main Categories of Resistors

• 1. Linear Resistors
• Those which obey Ohms Law
• Circuit Symbols
• Examples of linear resistors

9
Two Main Categories of Resistors

• 1. Linear Resistors
• Those which obey Ohms Law
• Circuit Symbols
• Examples of linear resistors

10
2. Non-Linear Resistors

• Those which consist of three types in common
  use
• a. photoresistors-light sensitive
• b. thermistors - heat sensitive
• c. voltage - dependent resistor
• a.Photoresistors- are also called photocells or
  light-dependent resistors (LDR)
• usually based on the fact that a film of
  cadmium sulfide has a high resistance in the
  absence of light but has a reduced resistance
  when light is directed on its surface.
• Circuit symbols
• Uses
• potential divider network to cause a
  voltage to change if the light falling on it
  changes
• by limiting the current, photoresistors are
  used as a switch
• used in automatic street light switching
  or parking light control.

11
b.Thermistor

• Thermistor or temperature-dependent resistor
  (TDR), change their resistance with change of
  temperature in a rather exaggerated way.
• Two types of thermistors
• 1. positive temperature coefficient (p.t.c)
• 2. negative temperature coefficient (n.t.c)
• Circuit Symbols
• n.t.c type- are supplied in many shapes and sizes
  from beads to larger rods or discs. As
  temperature increases, the resistance decreases.
• Applications car temperature gauge
• spontaneous
  combustion alarm
• control of heater
  element

12
c.Voltage-Dependent Resistor

• Sometimes called a metrosil, the voltage
  dependent resistor (VDR) has a resistance which
  decreases when supplied voltage increases. This
  change of resistance is not linear, doubling the
  voltage can decrease the resistance of one-tenth
  of its original value.
• Circuit Symbol

13
Activity 2. Hi friend, I want you to
develop your potential in music. I compose this
for you, I know you can sing it
well.Musical/Rhythmic Ability

• RESISTOR COLOR-CODING
• (Tune The Alphabet)
• Zero is black
• One is brown
• Red is 2
• Three orange
• Rap (at your own version)
• Four yellow The multipliers of the
  colors
• Green is 5 above are just the
  same,
• Six is blue oh yeah, but for gold its
  -1
• Violet 7 and silver is -2.
• The tolerance of brown is 1,
• Gray is 8 red is 2, orange is 3, 4
  yellow,
• White is 9 gold is 5, silver is 10, no
  color is 20!
• You can solve
• Resistors wise!

14
ACTIVITY 2 WRITE MY VALUE Direction
Summarize the values of the colors mentioned in
the song- Resistor Color Coding in the table
below.
Color Value for 1st 2nd digits Multiplier (x 10) Tolerance ()
1
2
3
4
5
6
7
8
9
10
11
12
13
15
Lesson 2- Color Coding For Resistors

• Because it is vital that resistors be
  matched to specific resistance requirements in a
  circuit,
• a clear method is needed for marking and
  identifying these devices. To overcome the
• problem, the electrical industry standardized
  with a system of color bands that provide
• visible identification of resistance values.
  These color bands comprise what is known as
• the resistor color code.
• Every resistor is identified by at least
  three color bands. Many resistors have a fourth
• band some have a fifth band.
• Always start reading from the band that is
  closest to the end of the resistor.

Red 2 The value of the
resistor is Violet 7
27 x 10 4 10 ohms Yellow 4
270 000 10 ohms Silver 10
16
What are bands for?

• 1st and 2nd bands represent a two- digit number
• 3rd band - is the multiplier
• 4th band (or the absence of this band) indicates
  the tolerance of the resistor
• Tolerance is the degree to which a resistor
  is permitted to vary from its value.
• 5th band - is required on resistors designed to
  meet military specifications. It indicates the
  reliability of the resistor.
• Reliability is measurement of the expected
  failure rate of these resistors per each one
  thousand hours of use.
• Examples of Resistors

17
Activity 3- COLOR- CODING RESISTORSMathematical
Ability

• A.Directions Compute the value of the resistors
  given their bands as follows

• Color
  Value
  
• Red, green, brown, gold
• Orange, black, black, silver
• Yellow, green, gold, gold
• Blue, white, violet
• White, brown, red, silver

• B. Decoding Resistors
• Direction Decode the color or bands of the
  resistor given their values.
• Value of the Resistor
  Color or Bands of the Resistor
• 840 5 ohms
• 13 10 ohms
• 5700 20 ohms
• 76 2 ohms
• 820 10 ohms

18
Lesson 3- Uses of Resistors

• Resistors are used in amplifiers.
• Resistors are used in bias networks.
• Resistors are used as feedback element.
• Resistors when combined with capacitors, they act
  as filters.
• Resistors reduced voltages by dissipating power
  and to discharge capacitors after power is
  removed.
• They are used in precision circuits to establish
  currents.
• Resistors are utilized to provide voltage ratios.
• In high voltage circuits, they are used to
  equalize current leakages.
• Name 5 devices or appliances that use resistors.

19
Enrichment ActivitiesDirections Choose at least
two (2) of the activities below. Let your teacher
check and evaluate your work.

• Visual/Spatial Ability
• Draw at least 5 resistors with
  different values.
• Bodily/Kinesthetic Ability
• Make a dance step of the song-
  Color Coding Resistors
• Naturalist
• Find out the element contents in a
  resistor.
• Interpersonal
• Work in groups to create an
  advertising campaign on how to overcome

20
Post-Test

• I. Multiple choice
• Direction Analyze each statement or phrase
  and write the letter of your choice on the space
  provided before the number.
• ___1. Metrosil is another name for
• A. photocell. B. thermistor C.
  voltage-dependent resistor
• ____2. Which is an application of thermistor?
• A. Switch B. Potential divider C.
  Car temperature guage.
• ____3. The circuit symbol for photoresistor is
• A.
• B.
• C.
• ____4. A standardized system of color bands that
  provide visible identification
• resistance values is called ________ color
  code.
• A. capacitor B. diode. C. resistor
• ____5. Resistors are used as/to

21
Post-Test

• ____7. Ohm is the unit of measure for
• A. current. B. resistance. C. voltage.
• ____8. A resistor with bands white, orange, red,
  gold has a value of ____ ohms.
• A. 9 200 5 B. 9 300 5
  C. 9 400 5
• ____9. Describe the colors of a resistor with a
  value of 41 20 ohms.
• A. yellow, black, brown
• B. brown, black, yellow
• C. yellow, brown, black
• ____10. A type of non-linear resistor that is
  being used in automatic street light
• switching is
• A. photocell. B. thermistor. C.
  voltage-dependent resistor.
• II. Matching Type
• Directions Match column A to column B. Write the
  letter of your choice on the space provided
  before the number.
• COLUMN A COLUMN B
• (color of the bands in a resistor)
  (numerical value of the band)

22
Key to Correction

• Pre-Test
• I. Multiple Choice II. Matching
  Type
• A 1. g
• B 2. i
• A 3. a
• C 4. f
• A 5. j
• A 6. b
• B 7. c
• A 8. e
• C 9. h
• B 10. d
• Post-Test
• 1. C 1. j
• 2. C 2. f

23
Key to Correction ACTIVITY 1- FIT ME!
T O L E R A N C E C
R E B L A C K
A D I O D E P
N G R A Y
S C L
I G I D
S I L V E R T R W
T E V O H
O H M R E S I S T O R I
R N O T
L B L U E
Y E L L O W
T R
A
B R O W N
G O L D
E
24
ACTIVITY 2 WRITE MY VALUE Direction
Summarize the values of the colors mentioned in
the song- Resistor Color Coding in the table
below.
Color Value for 1st 2nd digits Multiplier (x 10) Tolerance ()
1 Black 0 - -
2 Brown 1 X 10 1 1
3 Red 2 X 10 2 2
4 Orange 3 X 103 3
5 Yellow 4 X 104 4
6 Green 5 X 105
7 Blue 6 X 106
8 Violet 7 X 107
9 Gray 8 X 108
10 White 9 X 109
11 Gold X10 -1 5
12.Silver X 10 -2 10
13. No color 20
25
Activity 3- COLOR- CODING RESISTORSMathematical
Ability

• Key to Correction

• Color
  Value (in ohms)
  
• Red, green, brown, gold 250 5
• Orange, black, black, silver 30 10
• Yellow, green, gold, gold 4.5 5
• Blue, white, violet 690 000 000 20
• White, brown, red, silver 9 100 10

• B. Decoding Resistors
• Direction Decode the color or bands of the
  resistor given their values.
• Value of the Resistor Color or Bands of
  the Resistor
• 840 5 ohms gray, yellow, brown, gold
• 13 10 ohms brown, orange, black, silver
• 5700 20 ohms green, violet, red, (no color)
• 76 2 ohms violet, blue, black, red
• 820 10 ohms gray, red, brown, silver

26
References

• 1. Badrkhan, Kamiran S and Davir Larky.
  1984.Electronics Principles
• and Applications.Ohio South-Western
  Publishing Co. pp. 137- 146.
• 2. Physics -Science and Technology
  Textbook for Fourth Year
• 2004. Quezon City Book media Press, Inc.
• pp. 414-416.
• 3. dela Peña, Julieta D. et. Al. 1998. Science
  and Tehnology- Fourth Year . Quezon City
  Phoenix Publishing House, Inc.
• p. 213..
• 4. Sorra, Ma. Nora L and Monalisa R.
  Mercado.2000. Science Fundamentals for High
  School IV. Physics.
• Quezon City Trinitas Publishing, Inc. pp.
  283-287.
• 5. http// www.yahoo.com
• 6. http// www.google.com

27
Enrichment Activity

• Rubrics for Scoring
• 10 - perfect!
• 8-9 - almost perfect
• 6-7 - needs to be done better
• 4-5 - needs supervision
• 2-3 - not great, but be patient enough
• 0-1 - needs attention, supervision

28
Feedbacking

• Resistors are materials that impede the flow of
  current.
• There are two main categories of resistors
• 1. Linear resistors
• 2. Non-linear resistors
• A. photoresistors
• B. thermistors
• C. voltage-dependent resistors
• Resistor -Color-Coding
• A standardize system of color bands that
  provide visible identification of resistance
  value.
• Resistors are used in amplifiers.
• Resistors are used in bias networks.
• Resistors are used as feedback element.
• Resistors when combined with capacitors, they act
  as filters.
• Resistors reduced voltages by dissipating power
  and to discharge capacitors after power is
  removed.
• They are used in precision circuits to establish
  currents.
• Resistors are utilized to provide voltage ratios.
• In high voltage circuits, they are used to
  equalize current leakages.