Final answer:
The measured width of a barn with a steel tape on a very cold day will be slightly longer due to the contraction of the steel at lower temperatures, resulting in a tape that is shorter than its standard length.
Step-by-step explanation:
When you measure the width of an outdoor barn with a steel tape on a very cold day, your measured width will be a bit long. This is because materials tend to contract when they are cold, and a steel tape measure would be no exception. As the temperature drops, the metal in the steel tape contracts, shortening the tape slightly compared to its length at a standard temperature. Therefore, when you measure something with a contracted tape, you will record a slightly longer length since the tape isn't stretching as far as it would at a standard temperature. If you measured on an average-temperature day, the tape would be at its standard length and the measurement would be accurate. On a very cold day, you would need to take into account the contraction of the metal due to the temperature.