The Length Reading Generator draws the instrument a length is read from: a centimeter or inch ruler with an object lying along it, a 150 mm caliper with its jaws open to the reading you type, or a 0–25 mm micrometer. Close-ups of the scales keep every mark readable in print.
The caliper reads to 0.1, 0.05 or 0.02 mm, and exactly one mark on its sliding scale lines up with the main scale. The micrometer reads to 0.01 mm at its marks, or to an estimated 0.001 mm between them, with its thimble’s marks bunching toward its edges as on a real one. Hold a block, cylinder, ball or wire in the jaws, give the instrument a zero error for a correction question, and turn on the answer key to print the reading.
Copy the figure straight into a test, worksheet or slide, or download it as a PNG or SVG. Printing the page prints just the figure. Share link copies the page’s address with your settings in it, so anyone who opens it sees this exact figure, and presets save settings you use often in your browser. It’s free, with no sign-up.
Read the main scale at the sliding scale’s zero: the last millimeter mark before it. Then find the one mark on the sliding scale that lines up exactly with a main-scale mark, and add that many least counts. With the zero just past 23 mm and the 9th mark of a 0.05 mm scale lined up, the reading is 23 + 9 × 0.05 = 23.45 mm.
The smallest length it can read: one main-scale division less one division of the sliding scale. Ten divisions over 9 mm are 0.9 mm each, so the least count is 1 − 0.9 = 0.1 mm. Twenty over 39 mm (1.95 mm each, against 2 mm on the main scale) give 0.05 mm, and fifty over 49 mm give 0.02 mm.
Read the last mark showing on the sleeve: whole millimeters above the datum line, and the half-millimeter mark below it if it has appeared. Then add the thimble mark on the datum line, 0.01 mm each. A sleeve showing 7 mm and thimble mark 38 read 7.38 mm; with the 7.5 mark showing as well, 7.88 mm. When the datum line falls between two thimble marks, estimate how far, in tenths of a mark, for one more digit: 0.4 of the way from mark 38 to mark 39 reads 7.384 mm.
With its jaws closed, a caliper or micrometer should read zero. If it doesn’t, the reading it shows closed is the zero error, positive or negative, and you subtract it from every reading: an instrument that reads +0.10 mm closed and 23.45 mm on a block measures 23.35 mm. Turn on Also show it closed to draw the closed instrument above the measuring one.
Read to the smallest mark, then estimate one more digit. On a ruler marked in millimeters, that means reading to 0.01 cm, like 4.37 cm. On a ruler marked only every centimeter, read to 0.1 cm.
Physics Figures Length Reading Generator Physics Figures Length Reading Generator