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

[单选题]
A student measures a dil+kun)b,l 6x(g4 gpl(uu+qy j stand ;bwxg.0b( 9zrse+ pice four times. The readings are 37.8 cm, 37.9 cm, 38.1 cm, 38.2 cm. What is the best estimate of eg w9s;0bz( rbix.+dpthis 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 extremes (37.8 cm and 38.2 cmpzm5rk4 +a3t 7wta *ip) are both 0.2 cm away from the meanat rt*ip+5pa3m 47kw z. So C is the correct answer.