🔍 Key Concepts

• How to read a micrometer sleeve scale (the fixed, lower horizontal scale) in thousandths of an inch • How to read the thimble/rotating scale (vertical scale) and then the vernier scale for ten‑thousandths (0.0001 in) • Breaking .9453 inches into sleeve + thimble + vernier parts (.900 + .045 + .0003)

💭 Think About

• First decide what value the fixed sleeve scale is showing just to the left of the thimble edge. About how many hundredths or thousandths does that represent? • Next, look at the rotating thimble scale: which line on that scale is aligned exactly with the sleeve reference line? How many thousandths does that add? • Finally, on the vernier, which fine line lines up exactly with a line on the thimble scale, and what ten‑thousandths (0.0001) value does that correspond to?

✅ Before You Answer

• Be sure the sleeve reading you choose is just BEFORE the thimble edge, not past it • Confirm that the aligned thimble line plus the sleeve value total approximately 0.945 inches before adding the vernier • Check that exactly one vernier line lines up perfectly with a thimble line and that this adds 0.0003 in, not 0.0001 or 0.0005