Kognity IB Physics A.0 Measurements & Uncertainty (id: 420102d71)

[单选题]
The length of a pencil is measured using part of a metre rule thsmxr 2/,)xqzy at gc r,yq wew: ,3vlr+z a9+m+ddis graduated in millimetresm3 r+w q+yr, +edz ,vgl9:dwac, as shown below.

What is the length of the pencil?

A. $(6.00 \pm 0.10) \; cm$
B. $(6 \pm 0.1) \; cm$
C. $(6 \pm 0.05) \; cm$
D. $(6.00 \pm 0.05) \; cm$


参考答案:  A


本题详细解析:
With a millimetre scale we can take each rej2+j6f c1ohj oading to ±0.5mm, following the rule that the uncertainty is half the smallest division. So when we subtract our two readings to get the len6 foojjch+j21 gth of the pencil, we have to add the absolute uncertainties, giving 0.10cm. The length must be presented to the same number of decimal places as the uncertainty.