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

[单选题]
A student measures atfduewfu/hn:+ 3rx2 8 n9(dfi .w6 c2qsihav ujo x,8 l,zg;9avmu)3udistance four times. The readings are 37.8 cm, 37.9 cm, 38.1 cm, 38.ov g, ,6;lva8zwx a im)hu.9u2cj3squ2 cm. What is the best 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 extremev9 dd *gp /xbd7*efj0es (37.8 cm and 38.2 cm) are both 0.2 cm9v df0p/* bgxejdd7e * away from the mean. So C is the correct answer.