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

[单选题]
A student measures a distazwfiadenk s4lj2 t+pm67* ,t f/ tg6m2eh3f/znce four times. Theqxu mar i+*6v3 readings are 37.8 cm, 37.9 cm, 38.1 cm, 38.2 cm. What is the best estim+ *ua6xq rmiv3ate 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 extremestvfc2iuh,6)5c(nwog/+ m:,ffd mrvv (37.8 cm and 38.2 cm) are both 0.2 cm away from the mean. So C is the correct answevd6) u+,nv w,5 oci(:rgv f fmt/2hcmfr.