Question

Which is a derived unit? a.) kilogram b.) joule c.) micrometer d.) millimeter

Answer 1

Answer : The correct option is, (b) joule

Explanation :

Derived unit : Derived units are derived from some basic units.

From the given options, option a, c and d are the basics units. While the option b is the derived unit.

The derived unit Joule is the unit of work which is derived as,

$work=force\times displacement$

The unit of force is newton (N) and 1 N is equal to the $1\text{ Kg }m/s^2$

The unit of displacement is meter (m).

Now by putting these units in above formula, we get the unit of work.

$work=(1\text{ Kg }m/s^2)\times (m)=1\text{ Kg }m^2/s^2=Joule$

Hence, the derived unit is, joule.

Answer 2

Joule us a derived unit