Which of the following units is a derived unit?
second
meter
density
ampere

Answer : The correct option is, Density

Explanation :

S.I : It is known as the international System of Units. It is defined as a scientific method to express the magnitude of the several basics units.

There are seven basic units in the system from which the other units are derived.

The seven base unit are, meter for length, kilogram for mass, second for time, ampere for current, kelvin for temperature, mole for amount of substance and candela for intensity.

As per question, second, meter and ampere are the S.I units but the density is the derived unit.

Density : It is defined as the mass of a substance contained per unit volume.

The unit of mass is kilogram (kg) and the unit of volume is . So, the unit of density will be:

Formula used :

The unit of density is,

Hence, the derived unit is density.