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

[单选题]
The length of a pencil is measured usinwteyf- m-,ce 0qt /z0bg part of a metre ruleg x.) 7o*klrhqxwgprn):op)/t)8 o jk that is graduated in millimetres, as shown l.j k/ ) p7g)ng)qxr troh):*woxop8kbelow.

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 taugl q0.m r b6;df7w5j;-velszni;j t0ke each reading to ±0.5mm, following the rule thmzt sld f-0;g;0j5rvb7. e;l6ijunq w at the uncertainty is half the smallest division. So when we subtract our two readings to get the length 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.