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There are 2 types of units viz., the basic/elementary units for mass, distance and time and the compound/derived units such Newton, Joule, etc for physical phenomenon that are derived from the basic units.

So, 1 Newton is the amount of Force required to increase the velocity of 1 Kg of point mass by 1 m/sec in 1 sec, in the direction of the change in velocity. 1 Joule is the amount of work done when a force of 1 Newton moves any point mass by a distance of 1m.

For a unit of Joule to be used for a unit of Torque, you would need a unit of Torque to always perform 1 Joule of work, which is not true.