🔍 Key Concepts

• Reading a vernier caliper: main (fixed) scale first, then the vernier (sliding) scale • On an inch vernier caliper, the zero on the vernier tells you how many whole inches and tenths are passed on the main scale • The vernier division whose line best lines up with a main-scale line gives the fractional part to add

💭 Think About

• Look at figure B: Is the vernier zero between 3 and 4 inches? About where between them does it fall on the main scale? • Which numbered line on the vernier scale is exactly in line with a line on the main scale? How much is each of those vernier divisions worth in inches? • After you get the whole-inch part from the main scale and the decimal part from the vernier scale, which of the four choices is closest to that total?

✅ Before You Answer

• Be sure you read the last main-scale line to the LEFT of the vernier zero, not the one it is approaching • Confirm which vernier line is in perfect alignment with a main-scale line – ignore lines that are almost aligned • Multiply the aligned vernier division by the correct increment (e.g., 0.01 in or 0.02 in, depending on your caliper) before adding it to the main-scale reading