Kognity IB Physics A.0 Measurements & Uncertainty (id: d206553aa)

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本题目来源于试卷: Kognity IB Physics A.0 Measurements & Uncertainty，类别为 IBDP Physics

[单选题]
The time for two events, a an a*jnfov pasg95t21h 8d b, are measurekhc7vyx:8huo;xgcg9g : k;yk n(:l6yh2 /rk qd to be $(5.1 \pm 0.1)s$ and $(4.9 \pm 0.1)s$ respectively. In which of the following quantities is the fractional(percent) uncertainty the smallest?

A. $a+b$
B. $a-b$
C. $a \times b$
D. $a/b$


参考答案:  A


本题详细解析:
C and D will both have identical fractional uncertaintyrt/ox 9u:lz9 07z:ehix ga d5ies. They cannot both be the smallest, so they must both be incorrect. A and B will have the same : 5uz/yiozg7rxtld 9x :e0a9habsolute uncertainty (0.2 s), but A is a large number (10) compared to B (0.2). Hence fractional uncertainty of A is the smallest.