本题目来源于试卷: Kognity IB Physics A.0 Measurements & Uncertainty，类别为 IBDP Physics
[单选题]
The length of a pencil is measured using part of a measuring bva-*w ,(mmfqx(,d y dta v+zf. fcq qof0668r *bjsov,bpe as shown below , 6zjqf6vofb0r+* .oqvc f8 sb.  What is the length of the pencil?
A. $4.5 \pm 0.1 \; cm$
B. $11.5 \pm 0.2 \; cm$
C. $11.5 \pm 0.3 \; cm$
D. $11.5 \pm 0.5 \; cm$
参考答案: D
本题详细解析:
We should be looking at the cm scale! T i7oegm 5szytj,s/0 1khe uncertainty in a reading on a scale is usually taken as half the smallest division. Here the smallest division is 0.5 cm so we can read each point on the scale to an accuracy of 0.25 cm. To find the lengt jem/ kso5z1s, y0ig7th of the pencil we must take two measurements - one for each end of the pencil. This means that we must also add the uncertainties, giving an uncertainty of 0.5cm.
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Post time 2024-8-21 21:38:19