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 mea -lv0x8p /ra+ v inr5bcv*pb5csye-hvem 8(w)su +3e-nnypfz7 s 9kihf3 red using part of a measuring tape as shown below en-fhp i3n y9k7+zs 3f.  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 uncertaint8lsrcub1- gp( )y5. kurbv1a jy 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 as-urv5pu)1gk a8ryb (c1b j.lccuracy of 0.25 cm. To find the length 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