you measure the diameter of a circle then you calculate the radius of the circle using this diameter.

(1) Which one has a greater uncertainty, the diameter or the radius? Why?

you measure the radius of a circle then you calculate the diameter of the circle using this radius.
(2) Which one has a greater uncertainty, the diameter or the radius? Why?

(3) How about if you compare the relative uncertainties of the two cases mentioned? Justify.

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