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

[单选题]
A student measures a distance four tv7-aq 7t j7g;8dpkh (l bmful+-8mamgimbku28k 3 nf.bkfaq,5) u7cpmaes. The readings are 37.8 cm, 37.9 cm, 38.1 cm, 38.2 cm. What is the best estimate of thkn auu bkqcbam)f23,fp87.k5 is 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 extbv 6m .(f9 zj;4oywshlremes (37.8 cm and 38.2 cm) are both 0.of9b(y4 jvz l hm.ws6;2 cm away from the mean. So C is the correct answer.