[填空题]
The density of a solid sphere is measu+hig9q96l,;wa1 fb9 y5 qw*kc su ztznred with perco+;1:m;, zktkgh ieiwa( 1q4qhfjxr ;entage uncertainty of 5%. The radius of the spha fhk1; 4z q(th+g;qikjw; 1iomex r:,ere is 4.0 ± 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 debmiv6(.or m* *ah3 saensity of the material of which it is made: 6m( o.* shiarmbe3a* v$$M=\frac{4}{3} \pi r^3 \rho$$ 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 $(3 \times 5 \%)+5 \%=20 \%$