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

[单选题]
A student measures a distance fq8v:vav ,h2 6.j0ss*tikt rv8 sp cb6gmpu9n,qfuvc 2x. ,,hk* zz. hfour times. The readings are 37.8 cm, 37.9 cm, 38.1 cm, 38.2 cm. What is the best estimate ohuucx f,v2*gh kn,zpzq., m9. f 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 measuu;sa/u:d +mer-kzfnc/ vyev t. 5t :5urements is 38.0 cm. The extremes (37.8 cm and 38.2 cm) are both 0.2 cm awavu tcyfu5 ; :m+-: everta./ukdn5z/s y from the mean. So C is the correct answer.