Question

Measurement taken with Vernier caliper are as follows: \(1.21, 1.23, 1.24, 1.20\) mm. What can be the least count of Vernier Caliper?

• A. \(0.1\) mm
• B. \(0.01\) mm
• C. \(0.001\) mm
• D. \(0.0001\) mm

Hint:

The least count of an instrument can often be identified by {the smallest difference between successive experimental readings}.

Answer 1

The Correct Option is B

Concept:
The least count (L.C.)
of a measuring instrument is the smallest value that can be measured accurately. For a Vernier caliper: \[ \text{Least Count} = \text{Smallest difference between two consecutive measurable readings} \]
Step 1: Observe the Given Measurements
The recorded measurements are: \[ 1.20,\; 1.21,\; 1.23,\; 1.24 \text{ mm} \]
Step 2: Find the Minimum Difference Between Readings
Arrange the readings in ascending order and find the differences: \[ 1.21 - 1.20 = 0.01 \text{ mm} \] \[ 1.23 - 1.21 = 0.02 \text{ mm} \] \[ 1.24 - 1.23 = 0.01 \text{ mm} \] The smallest difference
between consecutive readings is: \[ 0.01 \text{ mm} \]
Step 3: Identify the Least Count
Since the Vernier caliper can measure changes as small as \(0.01\) mm, its least count must be: \[ \boxed{0.01 \text{ mm}} \]