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

[单选题]
A student measures a csst:gfkrw (7j80a2.jd i 5rq distance f+2laheqapr; ,+ q0x:.d iiomnx 1-qplour times. The readings are 37.8 cm, 37.9 cm, 38.1 cm, 38.2 cm. What is t qpqlha0xap;e-id1 :ril. m+,+xo nq 2he 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 extremes (37.8 cm anduvrc;w/y72o y 38.2 cm) are both 0.2 cm away from the mean. So C is the correct answcu 2 7owyvry;/er.