GATE 2024 MT – Question 64
A simple vertical casting gate has cross-sectional area 2 cm$^2$ and sprue height 10 cm. The filling time for a 40 cm × 20 cm × 10 cm mould is ______ s (one decimal place). Given: $g=980$ cm s$^{-2}$.
Practise this question in The GATE Grind →
Show answer and explanation
Correct answer: 27.0 to 30.0
Explanation
For the ideal constant-head model, gate speed is $v=\sqrt{2gh}=\sqrt{2(980)(10)}=140$ cm/s.
Flow rate is $Av=2(140)=280$ cm$^3$/s.
Mould volume is $40(20)(10)=8000$ cm$^3$.
Thus $t=8000/280=28.5714\ldots$ s, giving **28.6 s**.