Which of the following is not a basic unit of metric measure?

Which of the following is not a basic unit of metric measure?

• A. Seconds
• B. Meter
• C. Liter
• D. Grams

Answer: (A)

Understanding which units are base (fundamental) versus derived helps you quickly spot the correct choice. In SI, the base units define the seven fundamental quantities: length, mass, time, electric current, thermodynamic temperature, amount of substance, and luminous intensity. The meter is the base unit for length, the second for time, and the kilogram for mass. The liter is a unit of volume and is derived from cubic meters, so it is not a base unit. The gram is a unit of mass that is 1/1000 of a kilogram, so it is also not a base unit. Therefore, the not-basic units in the list are liters and grams, while seconds and meter are base units. The given answer contradicts SI conventions, since seconds is a base unit.

Understanding which units are base (fundamental) versus derived helps you quickly spot the correct choice. In SI, the base units define the seven fundamental quantities: length, mass, time, electric current, thermodynamic temperature, amount of substance, and luminous intensity. The meter is the base unit for length, the second for time, and the kilogram for mass. The liter is a unit of volume and is derived from cubic meters, so it is not a base unit. The gram is a unit of mass that is 1/1000 of a kilogram, so it is also not a base unit. Therefore, the not-basic units in the list are liters and grams, while seconds and meter are base units. The given answer contradicts SI conventions, since seconds is a base unit.