🔧 Vernier Caliper Experiment

Measure Diameter and Thickness with 0.01 cm Precision

✅ FREE Experiment • 📊 Interactive Simulation • 🎓 NEB Class 11 Practical

Interactive Simulation

Drag the vernier scale or use slider to measure different objects

Experiment Controls

Range: 0 - 10.0 cm

Current Reading
Main Scale Reading (MSR): 0.0 cm
Vernier Coinciding Division (VCD): 0
Least Count (LC): 0.01 cm
Total Reading: 0.00 cm

Real-Time Results

Main Scale (MSR)
0.0
cm
Vernier Division (VCD)
0
division
Total Reading
0.00
cm
Mean Diameter
0.00
cm

Observation Table

S.No. MSR
(cm)		 VCD VCD × LC
(cm)		 Total Reading
(cm)
No observations yet. Adjust the vernier and click "Take Reading"

📊 Mean Calculation

Mean diameter = 0.00 cm

Number of readings = 0

Accuracy = ±0.01 cm (Least Count)

📚 Theory & Concepts

What is a Vernier Caliper?

A Vernier Caliper is a precision measuring instrument used to measure internal and external dimensions (diameter, length, thickness, depth) with an accuracy of 0.01 cm or 0.1 mm. It was invented by French mathematician Pierre Vernier in 1631.

Principle of Vernier Caliper

The Vernier Caliper works on the principle that 10 divisions of the vernier scale are equal to 9 divisions of the main scale. This slight difference allows us to measure values smaller than the smallest division on the main scale.

Least Count Formula

LC = 1 MSD ÷ Number of VSD = 0.1 cm ÷ 10 = 0.01 cm

Where:
• LC = Least Count (smallest measurement possible)
• MSD = Main Scale Division (0.1 cm)
• VSD = Vernier Scale Divisions (10 divisions)

Reading Formula

Total Reading = MSR + (VCD × LC)

Where:
• MSR = Main Scale Reading (reading just before vernier zero)
• VCD = Vernier Coinciding Division (which vernier line matches main scale)
• LC = Least Count (0.01 cm)

Parts of Vernier Caliper

🔬 Procedure

  1. Determine the least count of the Vernier Caliper (LC = 0.01 cm)
  2. Check for zero error by closing the jaws completely
  3. Clean the object and jaws with a clean cloth
  4. Place the object between the external jaws
  5. Slide the movable jaw gently until it touches the object
  6. Tighten the locking screw to hold the position
  7. Note the Main Scale Reading (MSR) just before vernier zero
  8. Find which vernier division coincides with main scale (VCD)
  9. Calculate: Total Reading = MSR + (VCD × 0.01)
  10. Repeat 5 times at different positions for accuracy
  11. Calculate mean diameter from all readings

💬 Viva Questions & Answers

Q1: What is a Vernier Caliper?
A Vernier Caliper is a precision measuring instrument used to measure internal and external dimensions with an accuracy of 0.01 cm. It consists of a main scale and a sliding vernier scale.
Q2: Who invented the Vernier Caliper?
Pierre Vernier, a French mathematician, invented the Vernier scale principle in 1631.
Q3: What is the least count of Vernier Caliper?
Least Count = 1 MSD ÷ Number of VSD = 0.1 cm ÷ 10 = 0.01 cm = 0.1 mm
Q4: What is the principle of Vernier Caliper?
10 divisions of the vernier scale are equal to 9 divisions of the main scale. This difference allows measurements smaller than the main scale's smallest division.
Q5: What is zero error?
Zero error occurs when the zero mark of vernier scale doesn't coincide with zero of main scale when jaws are closed. It can be positive (zero of vernier right of main scale zero) or negative (zero of vernier left of main scale zero).
Q6: How do you correct zero error?
For positive zero error: subtract from observed reading. For negative zero error: add to observed reading. Corrected Reading = Observed Reading ± Zero Error.
Q7: What is Main Scale Reading (MSR)?
MSR is the reading on the main scale just before (to the left of) the zero mark of the vernier scale when measuring an object.
Q8: What is Vernier Coinciding Division (VCD)?
VCD is the division number on the vernier scale that exactly aligns or coincides with any division on the main scale.
Q9: Can we measure depth using Vernier Caliper?
Yes, the depth probe (tail) of the Vernier Caliper can measure the depth of holes, grooves, or containers accurately.
Q10: What is parallax error?
Parallax error occurs when the observer's eye is not positioned perpendicular to the scale while reading, causing incorrect measurement. Always view the scale at right angles.