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

[单选题]
A student measures a distn6/v +ku vuxny .ni ma2o65d l-84frcnz(td euh llmv v+-/-/mance four times. The readings are 37.8 cm, 37.9 cm, 38.1 cm, 38.2 cm. What is the besu+ h/evl--dlv mzmt/(t 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 38.0 cm. The extremes (378 44 xxqm+ (fvm exdh*z+oqj/h.8 cm and 38.2 cm) are both 0.2 cm away from the mean. So m*hmqzd 448(xh+/qoj v +fxex C is the correct answer.