Kognity IB Physics A.0 Measurements & Uncertainty (id: 87ba97ed9)

[单选题]
A student measures a distance fa0mmwoy9 m7oq pw)/ n*1m.dxl our times. The readings are 3 pdxlwl 5;lf7 f+f;.38futl6r)o vfrf7.8 cm, 37.9 cm, 38.1 cm, 38.2 cm. What is the best estim.5of 6vt r u)xr;f pll3ff ;7w8+lfdlfate of this measurement?

A. $37.8 \pm 0.2 \; cm$
B. $37.8 \pm 0.4 \; cm$
C. $38.0 \pm 0.2 \; cm$
D. $38.2 \pm 0.4 \; cm$


参考答案:  C


本题详细解析:
The mean of the measurements is 38.0 cm. The extremes (37hvtm-g e0hljvn 64g39 .8 cm and 38.2 cm) are both 0.2 cm away4nhgv -tm09 6hevl 3jg from the mean. So C is the correct answer.