Physics 2014 JAMB Past Questions - Question 2: What is the least possible error encountered when taking measurement with a meter rule ?

Correct Answer

A

Explanation

The precision expected when using metre rule to measure length is half the smallest division of the rule at both ends of the points. The smallest division of the rule is 1mm. Half of this at both ends is therefore 0.5mm x 2 = 1.0mm. This is the least possible error.The least possible error encountered when taking measurements with a meter rule (also known as a ruler or a tape measure) depends on the precision of the instrument itself and the skill of the person using it.

1. **Instrument Precision:** The least count or smallest division of the meter rule determines the smallest measurement increment it can reliably provide. For example, if a meter rule is divided into millimeters, the least count would be 1 millimeter. In this case, you can measure to the nearest millimeter, and the least possible error would be ±0.5 millimeters because you might round up or down.

2. **Human Skill:** Human error can also come into play. A person's ability to align the meter rule accurately with the object being measured and to read it precisely can introduce additional error. With careful practice and a steady hand, you can reduce this error, but it's still a consideration.

In summary, the least possible error when measuring with a meter rule is primarily determined by the instrument's least count and the user's ability to use it accurately. To minimize error, it's important to use the appropriate instrument for the level of precision required and to be as careful and consistent as possible when taking measurements.