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The dimension of a physical quantity is defined as the power to which the fundamental quantities are raised to express the physical quantity. The dimension of mass, length and time are represented as M, L and T respectively .
Now,
Power is defined as rate of doing work.
Power = work / time
Dimensional Formula of work= M1L2T-2
Dimensional Formula of Time is T
Dimensional Formula of Power
=Dimensional Formula of work/Dimensional Formula of Time is T
=M1L2T-2/T
= M1L2T-3
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