Kognity IB Physics A.0 Measurements & Uncertainty (id: 3dae35a97)

admin

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 twos4nsf(jq4 f d abh/d1do;-:l t l25d z/r ca8qrz8 6n j3qa,rqklengths 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 largest absolute uncert 5-gf n+ kctksaid(+;iainty 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%; B 0.5%; C 0.67%; and D 2%. Clearly D is the largf5n(+i +sdca ktgk; -iest.