Question

3. State the standard SI units of x and y, the coordinates of the centroid of an area.

4. State the standard SI units of a moment of inertia of an area.

Answer 1

SI system is also konwn as metric system and is used around the world. There are 7 basic units in the SI system. Meter is one of the unit which is used to measure the distance in SI system.

3.

Coordinates (x, y) of centroid of an area are the distances measured from the origin along x axis and y axis respectively. Thus their standard SI units will be in meter. i.e. x coordinate unit in meter as well as y coordinate unit in meter.

4.

We know, first moment of area = area * distance

And moment of inertia of an area is nothing but second moment of area i.e.

moment of inertia of an area = first moment of area * distance

= (area *distance) * distance.......(1)

We know, area is measured as the square of distance, then SI units of area will be (meter)2

Thus, from equation (1)

The standard SI units of moment of inertia of an area will be (meter)4