# EXPERIMENT 1 PRECISE MEASUREMENTS Micrometer Vernier caliper Objectives

EXPERIMENT # 1 PRECISE MEASUREMENTS Micrometer Vernier caliper

�Objectives: �To determine the diameter of a metal ball and the length of the cube using VERNIER CALIPER. �To measure the diameter of the wire using MICROMETER.

VERNIER CALIPER

PARTS OF A VERNIER CALIPER 1 - Outside jaws: used to take external measures of objects 2 - Inside jaws: used to take internal measures of objects 3 - Depth probe: used to measure the depth of objects 4 - Main scale (cm & inch) 5 - Vernier Scale 6 - Retainer: used to block movable part

Measuring Using the Vernier: • Keep the body to be measured between the fixed jaw and mobile jaw Without pressure on it. • Take the main scale reading. • The division of the vernier that coincides with any division on the main scale is also noted. This is the vernier scale reading. • Then, the measurement of the object will be = Main scale reading + (vernier scale reading x least count) Here, Least count = Value of One Main Scale Division / Total Number of Divisions on the Vernier Scale The units of measurement is in millimeters (mm).

For vernier caliper: Total reading = MSR + (VSR x LC) MSR = Main Scale Reading MSR = 2. 7 cm x 10 = 27 mm VSR = Vernier Scale Reading VSR = 1(5) = 5 x 0. 02 mm = 0. 1 mm LC = Least Count Total Reading = 27. 1 mm

Electronic vernier calipers are also available The procedure for taking measurements remains the same.

MSR =. 9 cm x 10 = 9 mm VSR =3. 6(5) = 18 x 0. 02 mm =. 36 mm Total Reading = 9. 36 mm

Dimension Trial No. THICKNESS OF THE CUBE 1 MSR VSR TOTAL =MSR + (VSR X LC) CORRECTED READING MEAN THICKNESS 2 3 Dimension Trial No. DIAMETER OF THE BOB 1 2 3 MSR VSR TOTAL =MSR + (VSR X LC) CORRECTED READING MEAN DIAMETER

SCREW GAUGE/ MICRO METER Micrometer: Is a tool designed to measure thickness of an object

�MEASURING USING THE MICROMETER: 1. Keep the object between the measuring jaws. 2. Bring the measuring jaws together by turning the screw until the object is clamped and the thickness to be read no longer changes. 3. Take the main reading and the head scale reading.

For micrometer: Total reading = MSR + (HSR x LC) MSR = Main Scale Reading MSR = 7 mm HSR = Head Scale Reading HSR = 0 x 0. 01 mm = 0 mm LC = Least Count Total Reading = 7 mm QUESTION 1

QUESTION 2 MSR = 8 mm HSR = 12 x 0. 01 mm = 0. 12 mm Total Reading = 8. 12 mm

QUESTION 3 MSR = _____________ HSR = _____________ Total Reading = __________

Electronic screw gauge is also available. The procedure for taking the measurements remains the same

Dimension Trial No. PSR HSR TOTAL =PSR + (HSR X LC) CORRECTED READING MEAN THICKNESS OF THE LENSE Dimension DIAMETER OF WIRE Trial No. PSR HSR TOTAL =MSR + (VSR X LC) CORRECTED READING MEAN DIAMETER

• Conclusion: The diameter of the metal ball is _______ The length of the cube is ______. The diameter of the wire is ______.

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