Question

SI unit of work is called a derived unit. why

Answer 1

Other quantities, called derived quantities, are defined in terms of the seven base quantities via a system of quantity equations. The SI derived units for these derived quantities are obtained from these equations and the seven SI base units. Examples of such SI derived units are given in Table 2, where it should be noted that the symbol 1 for quantities of dimension 1 such as mass fraction is generally omitted.

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Answer 2

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/s2. This unit is more commonly called a joule (J)

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