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

[单选题]
A student measures a dwik(s/f**rb distance four timfd 8;wsjkj8:aes. The readings are 37.8 cm, 37.9 cm, 38.1 cm, 38.2 cm. What is the best estimate of this measurementj8 ; j8ws:adfk?

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 mqpscj(g5u ;/6;a5uaja* 5hoi fpd0 n38.0 cm. The extremes (37.8 cm and 38.2 cm) are both 0.2 cm away from the mean. So C is the correct ;6cjsuj/5 m0ah;p*ag poanq5 d( ufi5answer.