A) 8
B) 4
C) 3
D) zero
Correct Answer: B
Solution :
[b] \[({{m}_{concrete}}+{{m}_{sawdust}})g=V{{\rho }_{w}}g\] \[2.4\times \frac{4}{3}\pi ({{R}^{3}}-{{r}^{3}})+0.3\times \frac{4}{3}\pi {{r}^{3}}=\frac{4}{3}\pi {{R}^{3}}\times 1\] or \[{{R}^{3}}=\frac{3}{2}{{r}^{3}}\] \[\therefore \,\,\,\frac{{{m}_{concrete}}}{{{m}_{sawdust}}}=\frac{{{\rho }_{concrete}}\frac{4}{3}\pi ({{R}^{3}}-{{r}^{3}})}{{{\rho }_{sawdust}}\frac{4}{3}\pi {{r}^{3}}}\] \[=\frac{2.4}{0.3}\frac{\left( \frac{3}{2}{{r}^{3}}-{{r}^{3}} \right)}{{{r}^{3}}}=4\]You need to login to perform this action.
You will be redirected in
3 sec