Answer:01
When you describe nature, and you need standard, useful units for everything you will see that these units are linked. So you start with defining base units that are simple:
kg, meter, second, Kelvin, …
Now other units will be automatically derived:
speed = distancetime , so the unit is ms
acceleration = speedincreasetime , so the unit is ms2
Force = Mass x acceleration, so the unit is kg.ms2
Pressure is Force/surface, so the unit is kgm.s2
You can define new simple units for this, but they are still derived from the base units:
Force: 1N=1kg.ms2
Pressure: 1Pa=1kgm.s2
2 Answer
In mechanics, work is defined as “force x distance”. Since energy can be measured as work, we can write energy = force x distance. Thus SI derived unit of energy has the units of newtons x meter or kg m2/s