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

[单选题]
A student measures a dis v* bio0)h2mj6emqg27omcb +ltance four times. The rea jnz7x8rxtwh 5 nz,-3(xmba1fdings are 37.8 cm, 37.9 cm, 38.1 cm, 3(z 1j3xa7-m xfnhtw5b,xrz8 n 8.2 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 iiys*lx d+ v s4-fj6fp:t7m6 x8muat3hs 38.0 cm. The extremes (37.8 cm and 38.2 cm) are both 0.2 cm away from the mean. So C is tstdtxf6:may -lp*ujxvm846s i73+ h f he correct answer.