A mould has a down sprue whose length is 20 cm and the cross-sectional area at the base of the down sprue is 1 cm\(^2\). The down sprue feeds a horizontal runner leading into the mould cavity of volume 1000 cm\(^3\). The time required to fill the mould cavity will be
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Using CGS units (cm, $\text{cm}^2$, $\text{cm}^3$, $\text{cm/s}^2$) for this problem avoids potential unit conversion errors.
Remember to use $g = 981\text{ cm/s}^2$ rather than $9.81\text{ m/s}^2$.