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

[单选题]
A student measures a distance fo5b8::jc)l+dd gmcn*s8cu 0knnrm zg 1ur times. The 5lt0199*d iauwc2vxlj:*ek jtd/ qpp readings are 37.8 cm, 37.9 cm, 38.1 cm, 38.2 cm. What is the best estimate of this dekl1tpw d 9u**:t px ljj2c0i v95qa/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 extrem zeao0dy8.-+f-ftj-5u xun l; i klgd:es (37.8 cm and 38.2 cm) are both 0.2 cm away from the mean. So 8fkzt.oelji-y lun:-g-dxf d ;+u0a5C is the correct answer.