[填空题]
The radius of a circlil4sgl/0z.ds (vdh w -e of wire is measured to be 1yoj9ucg 8pmjic r-)290.0 ± 0.5 cm. What is the percentage error in the area of the loop? % What is the percentage error in the circumference of the loop? %
参考答案: 空格1: 10.0
空格2: 5.0
本题详细解析: First calculate the percentage error in the ra, y6 c/*m6or9rpx;w/c t,ppm w6itrcndius of the loop: $$ \frac{\Delta \mathrm{r}}{\mathrm{r}}=\frac{0.5}{10}=5 \% $$ The area of a circle is $A=\pi r^2$ and so the percentage error on the area of the loop will be twice the percentage error of the radius, $\Delta A=10 \%$.