The S.I. units are preferred. There are other systems which remain of importance in various

parts of the world and in particular fields of activity. The M.K.S. absolute units, so far as mechanics

is concerned correspond with S.I. units and it seems possible that MKS units may continue in use

for sometime along with S.I. units. Detailed conversion tables from one system to another can be

prepared. To change over from MKS system to S.I., just remember the following points.

1. The unit of force in M. K. S. system is kilogram force (kg f) or simply (kg).

2. The unit of force in S.I. units is newton (N)

3. One kilogram-force= g newtons

4. The value of g =9·81 m s^{-2}

Therefore one kg f=9·81 N ________________________ (1)

For example, the unit of pressure in M.K.S. system is kg f/cm^{2} and convertion of 150 kg f/cm^{2} to

S.I. units is required.

Now,150 kg f/cm^{2} = 150 x 9.81 N / ( 10 mm )^{2}

＝14.715 N/mm^{2}=15 N/mm^{2}

Thus,we may conclude that the current metric unit of pressure, viz. one kg f/cm^{2} is equal to 1/10

N/mm^{2} approximately.

i.e. One kg f/cm^{2} = 1/10 N/mm^{2} ________________________ (2)