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

[单选题]
A student measures a distance fouy4xlvz/y vgzd/ ,:noa 63biw: r times. The readings arf :fyyk*6vxpcl ;g 3:)iw,fvre 37.8 cm, 37.9 cm, 38.1 cm, 38.2 cm. What is the :fvflx; ywy 3rkg6 *i,: f)pcvbest estimate 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 1k jh dh47cqq,38.0 cm. The extremes (37.8 cm and 38.2 cm) are both 0.2 cm away from the h1d,jkqc4q7hmean. So C is the correct answer.