NICET - Highway Construction Inspection Practice Exam

When measuring, if the tape is measured at 45 degrees Fahrenheit but calibrated for 68 degrees Fahrenheit, what is the likely condition of the measurement?

1. Correct measurement

2. Measurement is short

3. Measurement is long

4. Measurement is uncertain

The correct answer is: Measurement is long

When a tape measure is calibrated for one temperature but used in another, thermal expansion or contraction of the tape can lead to a discrepancy in measurements. Tapes are typically calibrated at a standard temperature, commonly around 68 degrees Fahrenheit, because materials expand and contract with temperature changes. When a tape that is calibrated at 68 degrees Fahrenheit is used at 45 degrees Fahrenheit, the tape would actually contract slightly due to the lower temperature. As a result, the distance measured using the tape would be shorter than the actual distance it is supposed to represent. Therefore, if the tape is not adjusted for the temperature difference, the measurement taken will end up being short, reflecting the reduced length of the tape at the cooler temperature. Understanding the impact of temperature on materials is crucial in construction and surveying, as it can affect accuracy and lead to potential errors if not properly accounted for.