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 t82wyxzkcyg -:: udle 6wo)bv hq-cg2)ln0d(i jz 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 largesqv,semj y))5c jle jg6j7lje s , 8)h4l2*xlkkt absolute uncertainty divided by the smallest measurement value. A and B have an a768yj)xs j,) gj4l2kq ll ehvjec5kmle*) ,jsbsolute uncertainty of 0.1 cm, while for C & D it is 0.2 cm. So the percentage uncertainties are: A 1%; B 0.5%; C 0.67%; and D 2%. Clearly D is the largest.
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