Question

A mould cavity of 1200 $c{m}^3$ volume has to be filled through a sprue of 10 cm length feeding a horizontal runner. Cross-sectional area at the base of the sprue is 2 $c{m}^2$. The acceleration due to gravity is 9.81 $m/s^2$.
Neglecting frictional losses due to molten metal flow, the time taken to fill the mould cavity is seconds (rounded off to 2 decimal places).

• A. 4.28

Answer 1

The correct option is A 4.28
$\text{Given data:}$

$\text{Volume of mould cavity (V) = 1200}c{m}^3$

$\text{Height of sprue}\left(h_s\right)\text{= 10 cm}$

$\text{Area of sprue at the bottom}\left(A_s\right)\text{= 2}c{m}^2$

$\text{g = 9.81}m/s^2$

$\text{Sprue feeds a horizontal runner:}$

$\text{Filling time required}{t}_f\text{= ?}$



$\text{By assuming top gate,}{A}_g=A_s=A_3=2c{m}^2$

$\text{Filling time,}$

$t_f=\frac{V}{A_g{V}_g}=\frac{1200}{2\sqrt{2\times 981}}=4.28s$