Write the steps to measure length using a ruler.

To measure the length of any material using the ruler, the given steps should be followed :

1. Place the ruler along the length to be measured, parallel to its graduation (the markings on a ruler). The ruler should be parallel to the length being measured.
2. Make sure that the zero mark of the ruler coincides with one of the ends of the length to be measured.
3. If the zero mark on a ruler is broken or unclear, another mark (say 1) can be taken as the starting point. Note this mark and subtract it from the final reading to get the accurate length.
4. For accurate measurements, the eye must be placed vertically above the mark. Viewing from other positions causes parallax error, making the reading appear more or less than the actual value.