Question

the volume of a circular iron rod of length 1 m is 3850cm^3 . find diameter

Answer 1

Let the radius be r cm
length=1m =100cm
$v = \pi {r}^{2} h \\ 3850 = \frac{22}{7} {r}^{2} \times 100 \\ {r}^{2} = \frac{3850 \times 7}{22 \times 100} \\{r}^{2} =12.25 \\ r = \sqrt{12.25} = 3.5 \\ \\ d = 2r = 2 \times 3.5 = 7cm$

diameter=7cm

Answer 2

$\red{heyy \: your \: answer \: is \: here} \\ volume \: of \: circular \: iron \: rod \: = 3850 {cm}^{3} \\ \pi {r}^{2} h = 3850 \\ {r}^{2} = \frac{3850}{\pi \: h} \\ {r}^{2} = \frac{3850}{ \frac{22}{7} \times 100} \\ {r}^{2} = \frac{3850 \times 7}{22 \times 100} \\ {r}^{2} = \frac{26950}{2200} \\ {r}^{2} = 12.25 \\ r = \sqrt{12.25} \\ r = 3.5 \\ diameter = 2r \\ 2 \times 3.5 \\ = 7cm$