1.

2.

3.

4.

5.

Why do we need to measure different physical quantities in real life?

1. Know the value of individual calibration in the ohmmeter scale.

An ohmmeter scale is nonlinear which means the value of one line or calibration may not be true to other lines.

It is therefore proper to assign values to every line for proper and accurate interpretation

The areas involved are 1.) 0- 2, 2.) 2-10, 3.) 10 -20, 4.) 20-50, 5.) 50 - 100, 6.) 100- 200, 7.) 200 - 300, 8.) 300 - 500.9.) 500-1K 10.) 1K-2K

2. The scale can be divided into ten areas where individual treatment has to be made.

Several mathematical computations will be involved to show the manner how values of individual lines are resolved.

3. Range multipliers: RX1, RX10, RX1K, RX10K

Range Multiplier- The portion of the ohmmeter where the actual reading is being multiplied.Note: If Rx is greater than 1,000 ohms, and the R x 1 range is being used, the ohmmeter cannot measure it.

Scale Reading

Student’s Activity

Scale Reading

Divide the class into five groups.

Identify the value of each line(calibration).

Group 1: 0-2 area and 2-10 area

Group 2: 10-20 and 20-50

Group 3: 50-100 and 100-200

Group 4: 200-300 and 300-500

Group 5: 500-1000 and 1000-2000

Each group will identify the value of each line/calibration in every area assigned to them.

Group 1: 0-2 area and 2-10 area

Group 2: 10-20 and 20-50

Group 3: 50-100 and 100-200

Group 4: 200-300 and 300-500

Group 5: 500-1000 and 1000-2000

1.) 0- 2, Value of 1calibration = line distance / total calibrations involved For 0- 2: Line distance = 2 Total no. of cal = 10 Value of 1 line = 2/10 = 0.2 0.2, 0.4, 0.6, 0.8, 1, 1.2, 1.4, 1.6, 1.8, 2

1.8

1.) 0- 2, Value of 1 line = 2/10 = 0.2

1.4

1.6

1

1.2

0.6 0.8

2

0.4 0.2

2.) 2 - 10, Value of 1calibration = line distance / total calibrations involved For 2- 10: Line distance = 8 Total no. of cal = 16 Value of 1 line = 8/16 = 0.5 2.0,

49.

6.5

1.) 2- 10, Value of 1 line = 8/16 = 0.5

5.5 6 4.5 5 3.5 4 7

3 2.5

7.5 8

8.5 9

9.5

10

49.

3.) 10- 20, Value of 1calibration = line distance / total calibrations involved For 10- 20: Line distance = 10 Total no. of cal = 10 Value of 1 line = 10/10 = 1 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20

50.

4.) 20- 50, Value of 1calibration = line distance / total calibrations involved For 20- 50: Line distance = 30 Total no. of cal = 15 Value of 1 line = 30/15 = 2 20, 22,

5.) 50- 100, Value of 1calibration = line distance / total calibrations involved For 50 - 100: Line distance = 50 Total no. of cal = 10 Value of 1 line = 50/10 = 550, 55,

6.) 100- 200, Value of 1calibration = line distance / total calibrations involved For 100 - 200: Line distance = 100 Total no. of cal = 5Value of 1 line = 100/5 = 20100, 120,

7.) 200- 300, Value of 1calibration = line distance / total calibrations involved For 200 - 300: Line distance = 100 Total no. of cal = 2Value of 1 line = 100/2 = 50200, 250,

8.) 300- 500, Value of 1calibration = line distance / total calibrations involved For 300 - 500: Line distance = 200 Total no. of cal = 2Value of 1 line = 200/2 = 100300, 400,

9.) 500- 1K, Value of 1calibration = line distance / total calibrations involved For 500 – 1K: Line distance = 500 Total no. of cal = 1Value of 1 line = 500/1 = 500500, 1000,

10.) 1K-2K, Value of 1calibration = line distance / total calibrations involved For 1K-2K: Line distance = 1000 Total no. of cal = 1Value of 1 line = 1000/1 = 10001000, 2000,

AREAS VALUE PER LINE

1. 0 – 2 ____________

2. 2 – 10 ____________

3. 10 – 20 ____________4. 20 – 50 ____________

5. 50 – 100 ____________

6. 100 – 200 ____________

7. 200 – 300 ____________

8. 300 – 500 ____________

9. 500 - 1K ____________

10. 1K - 2K ____________

0.2Ω

1Ω

2Ω

5Ω

20Ω

50Ω

100Ω

500Ω

1KΩ

0.5Ω

250Ω1.___1.2KΩ2.___

650Ω3.___

460Ω4.___

24Ω5.___

15KΩ6.___

85Ω7.___

35KΩ8.___

20Ω9.___

8Ω10.__

Range Multiplier: Instructions: Two items for each group 1.Identify the resistance 2.Compute using the assigned range multiplier.

250Ω1.___1.2KΩ2.___

650Ω3.___

460Ω4.___

24Ω5.___

15KΩ6.___

85Ω7.___

35KΩ8.___

20Ω9.___

8Ω10.__

QUIZ

400Ω1.___ 140Ω2.___

65Ω3.___

400Ω4.___

220Ω5.___

100Ω6.___

700Ω7.___

400Ω8.___

250Ω9.___

1KΩ10.__

#1-#3 (X1), #4-#6 (X10), #7-#9 (X100) #10 (X1K)

Directions: Identify the pointer reading and compute. Write your answer in ¼ sheet of paper. (2 points each reading.

Homework

Do a research work.1.Technical Drawing in Electronics2.Schematic and Pictorial Diagrams3.Schematic Symbols