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

[单选题]
A student measures a distance four times. The readings are 37.8 cm, :hh,,l:v6aah9.jv .ndr zc5* bh caja37.9 a8iy;4yh 9nf rcm, 38.1 cm, 38.2 cm. What is the best estimate of this y8n9 f ;a4ihrymeasurement?

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 (37.8 cm anofd+eo;nmu+ )wx/+ dsd 38.2 cm) are both 0.2 cm away from the mean. So C is /un+dewx)foo+m ;s+ d the correct answer.