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 tape :ob*irl)sm*cw+ s z-fas shown be 8navyheejz 4 9g(tjk t0ts17f0hp8( klow 4 0 ya(gv0kjh t9e1k(hf8jzt8s7tenp.  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! The uncx6,z nuh j4ws.wy t:b6j:3qyz ke1; mkk2 qsw:ertainty 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 length of the pencil we must take two measurements - one for ea;qxykkhb jwqn4m. :3yktw ws6:,21u:e6zz js ch 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