Question

uncommon unit of length in the metric system
which of the following is not a commonly used unit of length in the metric system?
multiple choice
centimeter
millimeter
micrometer
electrometer
nanometer

Explanation:

To determine which is not a common metric length unit, we analyze each option:

• Centimeter: Commonly used (1 cm = 0.01 m).
• Millimeter: Commonly used (1 mm = 0.001 m).
• Micrometer: Used in scientific contexts (1 μm = 10⁻⁶ m).
• Electrometer: A device to measure electric charge/potential, not a length unit.
• Nanometer: Used in nanoscience (1 nm = 10⁻⁹ m).

Answer:

D. electrometer