[填空题]
The density of a solid sphere is y*wyafz: 4;vi 3g.bzcmeasured wk cjaec m9 ;i+l ibz)icdvn3u)c.y 427ith percentage uncertainty of 5%. The radius of the sphere is 4.0 ± 0.2 cm. What is the percentage uncertainty ivi)kymc7cni iuz 2 +a9)c4bcl; 3.dejn the mass of the sphere? % (Please do not include the % simbol in the blank)
参考答案: 20.0
本题详细解析: The mass of the sphere can be cax5oo; ll- y/bplculated by multiplying its volume by the density of the material of -oy/l l px5bo;which it is made: $$M=\frac{4}{3} \pi r^3 \rho$$ so the percentage uncertainty in $M$ is $$\frac{\Delta M}{M}=3 \frac{\Delta r}{r}+\frac{\Delta \rho}{\rho} .$$ The percentage uncertainty in $r$ is $5 \%$, so the percentage error in $M$ is $(3 \times 5 \%)+5 \%=20 \%$
Post time 2024-8-21 21:38:19