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

[单选题]
A student measures a dis)kr34ua u n(t,zc6 p14b+a z-vagajnt tance four times. The readings are 37.*r(f ,nuio :muagv +;i8 cm, 37.9 cm, 38.1 cm, 38.2 +*fgi:on,( iv; uaurmcm. 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 extremey) qubllr .-dh3id co ()w;+cbs (37.8 cm and 38.2 cm) are both 0dwb hdq +cl ;(ycb))l.i-ou3r.2 cm away from the mean. So C is the correct answer.