[填空题]
The density of a solid qzrog2 j a6-4esphere imrfe71 w,2 n0 yj1glagbvw;l9s measured with percentage uncertainty of 5%. The radius of the sphere is f;jl7beny,av1 g1 9mlw0r2g w4.0 ± 0.2 cm. What is the percentage uncertainty in 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 calculated by multiplying its volume by the d1jj8tfz4 td8mwfy )l/ni7h8eensity of the material of which it i87hz/iyj 8j f)ln d8ef4tt1mws 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