Which Object is Closest in Length to a Micrometer?

A SUBMARINE? Submarines vary in length, depending on their use. Nuclear-powered attack submarines typically measure about 90 meters. Ballistic missile submarines are longer--about 140 meters.

AN ANT? The length of ants varies, but none is as small as a micrometer. Pharaoh ants measure about 1 millimeter, whereas ponerine ants, found in the tropics, are over 25 millimeters long. (A millimeter is one-thousandth of a meter.)

THE DIAMETER OF A HUMAN HAIR? This measures 80-100 micrometers. (A micrometer is one-millionth of a meter.)

A VIRUS? Viruses measure in the range 0.02-0.25 micrometers--closer to a micrometer than the other items in this list.

Fact: Another name for micrometer is "micron."