🔍 Key Concepts

• Review how to read a vernier micrometer: sleeve (barrel) scale, thimble scale, and vernier scale for ten‑thousandths of an inch. • Remember that on a standard 0–1 inch micrometer, each number on the sleeve usually represents 0.1 in, each small sleeve division 0.025 in or 0.025/0.050 depending on design, and each division on the thimble is typically 0.001 in. • The vernier scale on the sleeve lets you add the final 0.0001 in by finding which vernier line lines up exactly with a thimble line.

💭 Think About

• First, decide what the largest full value is that has already passed the reference line on the sleeve in figure C. Which tenth and which 0.025/0.050 increment are clearly visible? • Next, look at the thimble: which graduation on the thimble scale lines up with the horizontal reference line on the sleeve? That gives you the thousandths digit. • Finally, examine the vernier scale on the sleeve: which vernier graduation lines up exactly with a mark on the thimble? Use that to choose the correct ten‑thousandths digit and compare it to the answer choices.

✅ Before You Answer

• Be sure the sleeve reading you pick matches the whole and hundredth digits in the answer choices (0.42, 0.45, 0.46, or 0.46+). • Confirm that the thimble line you use is the one exactly on the reference line, not the closest one above or below it. • Double‑check which single vernier line is in perfect alignment; that will determine the last digit (the 0.000x place) and should match only one of the four options.