本题目来源于试卷: Kognity IB Physics A.0 Measurements & Uncertainty,类别为 IBDP Physics
[单选题]
A student measures twat5 m *4e(zyio ,tdh5vdvr1 v 0h-6hh1gcl at36 9wk ,u)dzdxro lengths as follows: $$a = (10 \pm 0.1) \; cm$$ $$b = (20 \pm 0.1) \; cm$$ Which of the following quantities has the largest percentage uncertainty?
A. $a$
B. $b$
C. $a+b$
D. $a-b$
参考答案: D
本题详细解析:
The largest percentage uncertainty will result from the lars;ecf r ; c0m3mmf)kf lz.vefy ql27),gest absolute uncertainty divided by the smallest measurement value. A and B have an absolute uncertainty of 0.1 cm, while for C & D it is 0.2 cm. So the percentage uncertainties are: A 1%; s);2reqm3k7 lm yf.,mvcc;0 fl) efzf B 0.5%; C 0.67%; and D 2%. Clearly D is the largest.
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