Notes on Vernier Calipers

Introduction to Vernier Calipers

• Purpose: Vernier calipers are precision instruments used for measuring dimensions.
• Components:
  • Two sets of jaws for holding objects.
  • Two scales:
    • Main Scale: Measured in millimeters and centimeters.
    • Vernier Scale: Measured in divisions.

Functionality

• Main Scale: Fixed in place.
• Vernier Scale: Movable, enables precise measurement.

Measurement Process

• Object Placement: Objects can be placed between the jaws in various orientations (vertical, horizontal).
• Least Count (Vernier Constant):
  • Denoted as VC, it is the smallest value the caliper can measure.
  • Calculate by comparing scale divisions:
    • 10 Vernier scale divisions = 9 Main scale divisions.
    • 1 Main scale division = 1 mm.
    • 1 Vernier scale division = 0.9 mm.
  • VC Calculation:
    • VC = 1 Main Scale Division (MSD) - 1 Vernier Scale Division (VSD) = 0.1 mm.

Zero Error

• Definition: Occurs when zero points of the scales do not align.
• Correction: Ensure zeros align perfectly; no zero error is present in the example.

Measuring Process Example

1. Place Object: Tube placed horizontally between jaws.
2. Align Scales:
   • Main scale reads 6.6 cm.
   • Vernier scale coincides at division 2.
3. Calculate Length:
   • Convert Vernier reading to mm by multiplying by VC.
   • Add to main scale reading: 6.62 cm (final length).

Mean Length Calculation

• Used for increased accuracy by taking multiple measurements.

Additional Measurements

• External/Internal Diameter:
  • Use jaws to measure diameters by placing the tube in different positions.
• Calculations:
  • Mean internal and external diameters calculated from multiple readings.
  • Volume Formula: Used to find volume; example result is 35.94 cm³.

Mass and Density

• Mass of Tube: 10.1 grams.
• Density Calculation:
  • Use formula: Density = Mass/Volume.
  • Example density: 0.29 g/cm³.