Question

Does every physical quantity need to have a dimension?

What is the error in the area

Answer 1

1)

No,every physical quantity need not to have dimension

Example :

Angle
No dimension, but have a unit(radian)




2)

Consider a rectangle

Area = Length × Breadth


But % error in area is

%error in length + %error in Breadth


That's why 2% +2 % = 4%





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