What is VC and LC in a vernier caliper

VC (Vernier Constant) and LC (Least Count) are two terms for the same concept the smallest measurement a vernier caliper can resolve. Both represent the value of one vernier scale division expressed in actual measurement units. The least count/vernier constant is calculated as: LC = (Smallest main scale division) ÷ (Number of vernier divisions), or alternatively, LC = 1 MSD - 1 VSD.

The terminology varies by region and educational tradition: "least count" is more common in practical engineering and workshop contexts, while "vernier constant" appears more frequently in physics education and theoretical discussions of the vernier principle. Regardless of terminology, this value represents the fundamental precision limit of the instrument—a caliper with LC/VC = 0.02 mm can distinguish measurements differing by 0.02 mm, but attempting to measure differences smaller than this exceeds the instrument's capability. For a standard 0.02 mm vernier caliper, each vernier division represents 0.02 mm, so the 5th line indicates 0.10 mm beyond the main scale reading, the 10th line indicates 0.20 mm, the 25th line indicates 0.50 mm, and so forth. Understanding that VC = LC helps avoid confusion when encountering different textbooks or regional terminology while maintaining the practical knowledge that this value defines your measurement resolution.