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

[单选题]
A student measures a dis6vd1lwmh p3sn4y t*0za;m/mbtance four times. The readings are 37.8 cmk*yv)eur z+ c-r*:axg , 37.9 cm, 38.1 cm, 38.2 cm. What is the best estimate of this*g*re :-z) y+vakruxc 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 extrem7/qcq rp;r 6:fsg to5mes (37.8 cm and 38.2 cm) are both 0.2 c:7qsr omr; gpt/5qf 6cm away from the mean. So C is the correct answer.