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

[单选题]
A student measures a distance four times. The readz5rv4t df r8gos8e-(hings jn0lo 2q*f lz2dssh(h p00:oeare 37.8 cm, 37.9 cm, 38.1 cm, 38.2 cm. What is theq:2l epsn *2hfz00hod (l osj0 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 extremes grh- ot(izrx3ht5f0;0q ;, k tcw;yws (37.8 cm and 38.2 cm) are both 0.2 cm away from the mean. So C is the correctk5rxhs ; ;q,ft-y w3 ritg0h;wc(zot0 answer.