The document discusses various measuring instruments used in applied science physics, including the vernier caliper, micrometer, dial caliper, spherometer, thermometer, and galvanometer. It explains how to use each instrument, read measurements, and determine the least count or smallest unit of measurement. Examples are provided for measuring length, diameter, depth, and other quantities. References for additional information on the instruments are listed at the end.

1. Measuring Instruments
Course: Diploma
Subject: Applied Science Physics
Unit: I
Chapter: III

2. Use of Vernier Caliper
Vernier Caliper
can be used to
measure diameter,
thickness very
accurately.
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3. 2

4. 0 cm 2 cm1 cm
0 10
Main Scale
Vernier Scale

5. Main Scale
3

6. Vernier Scale4

7. How to read the result
of measuring by using
the Vernier caliper

8. What is the result of measuring ?
5

9. What does it mean ?
6

10. 6 mm
7

11. What does it mean ?8

12. ( 2 x 0.1 ) mm
9

13. 6 mm
( 2 x 0.1 ) mm
The result of measuring is ( 6 mm + 0.2 mm ) = 6.2 mm
10

14. What is the result of measuring ?
11

15. The result of measuring is :
( 3 mm + ( 7 x 0.1 ) mm ) = 3.7 mm

16. 0 cm 2 cm1 cm
0 10
Main Scale
Vernier Scale
X 0.1 mm
Least Count = Value of the smallest division on MS/
Total number of division on VS
L.C = 1mm / 10 = 0.1 cm / 10 = 0.01cm

17. 0 cm 2 cm1 cm
0 4 862 10
Main Scale
Vernier Scale
X 0.05 mm

18. Measuring Internal Diameter
Use the inside
jaws of the
caliper as shown
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19. Measuring External Diameter
Use the outside jaws of
the caliper as shown
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20. Measuring Height of Bar.
14

21. Measuring Depth of a Hole
Use the depth
gauge of the
caliper as shown
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22. Measuring Instruments
• Vernier Caliper
• (a) Positive zero error
• Zero error = +0.04 cm.
16

23. Measuring Instruments
• Vernier Caliper
(b) Negative zero error
• Zero error = -0.02 cm.
17

24. Structure of the Micrometer
18

25. Scale description : Main scale & Circular scale
19

26. Least Count
• Least Count = Pitch of the Micrometer / Total
number of circular scale division
• Least Count = 1 / 100 = 0.01mm
= 0.001cm
20

27. 21

28. Measuring Instruments
22

29. Dial Caliper
The dial Caliper
has seven main
components:
a slide scale,
lock screw,
thumb adjustment
wheel, measuring
jaws (inside &
out), dial with
measurements of
0.001 inch, depth
rod and a bezel.23

30. Dial Caliper
Try this one
24 25

31. Dial Caliper
• Answer is
• 1.931

32. Read the Measurement 1
26

33. Read the Measurement 2
27

34. Read the Measurement 3
28

35. Read the Measurement 4
29

36. Read the Measurement 5
30

37. Description of the Spherometer
• Instrument that measures the surface power (D)
associated with the lens surfaces.
31

38. Functional Principle
Supporting the legs on the lens surface, the
movement of the center leg, is translated to the
scale, giving the value of the surface power of the
surface.
Positive value in
convex surfaces.
Negative value in
concave surfaces.
32

39. Zero error
Adjustment or Calibrating the instrument to zero:
When placing the instrument on a flat polished surface,
the scale must mark 0.00 D.
If not, all previous measurements will be affected by
this value.
The measurement will be a result of the following
equation:
Psur: Value given by spherometer when place on flat
surface.
Psph: Value given by spherometer when placed on one of
the curved surfaces of the lens.
surPspherePP 

40. A thermometer
is an instrument
that is used to
measure
temperature.

41. The temperature tells us how
hot or cold something is.
33

42. Temperature
is measured
using two
scales:
Celsius and
Fahrenheit.
212100 C F

43. Galvanometer
• The galvanometer is the "classic" device to
measure current
• Based on the fact that a wire carrying current
in a magnetic field feels a force
43

44. • The current flows through a coil in a
magnetic field
• The coil experiences a torque proportional to
current
• The movement of the coil is "opposed" by a
spring
• The deflection of the needle is proportional
to current
44
34
35
36

45. • Rsh = "shunt" resistance
• The current I divides itself between the
coil and the shunt
– I = IC + Ish
• By Ohms's law, Vab = IC RC = Ish Rsh
• Ish = IC (RC/Rsh)
• I = IC + Ish = IC (1 + RC/Rsh)
 If RC and Rsh are known, measuring IC is
equivalent to measuring I
• Furthermore, I is still proportional to IC, which is
proportional to the deflection of the needle
• Thus, by "switching in" different shunt resistances I
can effectively change the "range" of my current
measurement
37

46. Electrical Measuring Instruments
 Ammeter
38

47. Electrical Measuring Instruments
 Voltmeter
39

48. 40 41
42

49. 43
44
45

50. 46 47
48

51. 43
49
5352
50
51

52. REFERENCE BOOKS AUTHOR/PUBLICATION
ENGINEERING PHYSICS S S PATEL (ATUL PRAKASHAN)
MODERN ENGINEERING
PHYSICS
A S VASUDEVA
ENGINEERING PHYSICS K. RAJGOPALAN

53. Image reference links
1. http://www.slideshare.net/stootypal/vernier-caliper
2. http://www.tutorvista.com/content/physics/physics-i/measurement-and-
experimentation/vernier-callipers.php
3. To 11) http://i.imgur.com/2QqIQsU.png
12. http://postimg.org/image/56z59zrtp
13. http://postimg.org/image/hkbzgwhi5
14. http://www.muelaner.com/wp-content/uploads/2013/07/Calipers-Bolt2.png
15. http://postimg.org/image/8f3mn1e3h
16. http://i.imgur.com/V5pHuiR.png
17. http://i.imgur.com/7TShrLa.png
18. http://www.technologystudent.com/equip1/microm1.htm
19. http://www.indiastudychannel.com/attachments/Resources/143680-5126-Micrometergauge.jpg
20. http://www.cyberphysics.co.uk/practical/skills/micrometer2.gif
21. http://i.imgur.com/cxlIcvh.png
22. http://www.tutorvista.com/content/physics/physics-i/measurement-and-
experimentation/screw-gauge.php
23. http://0801.nccdn.net/1_5/2ff/292/391/dial-calipers.png
24. http://www.pixentral.com/pics/1CpY49KAqUFdhu88HhJTCL87z92J.png
25. http://i.share.pho.to/1b2ffae6_o.png
26. http://i.share.pho.to/dc6d8ee9_l.png
27. http://i.share.pho.to/7891c224_l.png
28. http://i.share.pho.to/38135259_o.png
29. http://i.share.pho.to/cb289234_o.png
30. http://i.share.pho.to/79e115ad_l.png
31. http://www.phys4arab.net/vb/showthread.php?t=30682

54. Image reference links
32. http://i.share.pho.to/9e2475b4_o.png
33. http://i.cubeupload.com/ERLcXH.png
34. To 36) http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/galvan.html
37. http://i.cubeupload.com/ERLcXH.png
38. http://i.cubeupload.com/7Kmkuj.png
39. http://i.cubeupload.com/pMmBAH.png
40. http://i.cubeupload.com/Z74xh1.png
41. http://cubeupload.com/im/M19NIc.png
42. http://cubeupload.com/im/CFIlLm.png
43. http://cubeupload.com/im/dk5I7m.png
44. http://i.cubeupload.com/xs7kyV.png
45. http://carcraftstore.com/images/products/thumb/AM3586.jpg
46. http://i.cubeupload.com/2zVJ6H.png
47. http://i.cubeupload.com/5pAyyo.png
48. http://cubeupload.com/im/UlwSGc.png
49. http://i1.olxthailand.com/df/0/ui/post/2014/10/02/8/t/f4c0fe31a19370caec10864f7b35c194.jp
eg
50. http://static.coleparmer.com/large_images/90000_53.jpg
51. http://www.entest.net/product_images/j/372/312FC__10343_thumb.jpg
52. http://dicoworldwide.com/picoasi-2.htm
53. http://imgur.com/lj2uzNU

55. END