Question

5. The volume of a circular iron rod of length 1m 3850 cm^3. Find its diameter.
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Answer 1

$\bigstar\huge\bf\underline{\underline{answer:-}}$

$\bigstar\bf\underline{\underline{Given:-}}$

$\mapsto$ The volume of circular iron rod of length 1m is 3850cm³

$\bigstar\bf\underline{\underline{To \ find:-}}$

$\mapsto$ The diameter

$\bigstar\bf\underline{\underline{Solution:-}}$

Given that the length of the circular rod = 1 m = 100 cm

Volume of the rod = 3850cm³

Volume of the cylinder = $\sf\pi r^{2}h$

Where r is the radius of the cylinder and h is the height or length of the cylinder

$\hookrightarrow\sf\pi r^{2}h \ = \ 3850$

$\hookrightarrow\sf \frac{22}{7}\times r^{2} \times 100 \ = \ 3850$

$\hookrightarrow\sf r^{2} \ = \ \frac{3850\times7}{22\times100}$

$\hookrightarrow\sf r^2 \ = \ \frac{1225}{100}$

$\hookrightarrow\sf r  = \ \sqrt{\frac{1225}{100}}$

$\hookrightarrow\sf r \ = \ \frac{35}{10}$

$\hookrightarrow\sf r \ = \ 3.5$

$\implies\boxed{\bf Radius \ = \ 3.5cm}$

Diameter = 2 × radius

$\implies2\times3.5$

$\implies\sf 7cm$

$\boxed{\boxed{\bf Diameter \ = \ 7cm}}$