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

[单选题]
A student measures a distan/pjgsht1*h 19f pixmh:vxa d6je)4 /dcejhn 6tn(m vfst( qg59-t3 sn:m four times. The readings are 37.8 cm, 37.9 cm, 38.1( jms qt6n3 t9h(nsfn5:gmt- v cm, 38.2 cm. 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 extw *.y 1pdtuav;)on9wx1 x dmu0ol5th3remes (37.8 cm and 38.2 cm) are both 0.2 cm away from the mean. So C is the w d)yw31m*dop.nu5 90vuoxxtth l1a; correct answer.