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A 200 mm long down sprue has an area of crosssection of 650 mm2 where the pouring basin meets the down sprue (i.e. at the beginning of the down sprue). A constant head of molten metal is maintained by the pouring basin. The molten metal flow rate is 6.5 × 105 mm3/s. Considering the end of down sprue to be open to atmosphere and acceleration due to gravity of 104 mm/s2, the area of the down sprue in mm2 at its end (avoiding aspiration effect) should be
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- 650.0
- 350.0
- 290.7
- 190.0
- 650.0
Correct Option: C
Here, Flow rate = 6.5 × 105 mm3 /s
A1V1 = 6.5 × 105
V1 = 1000 mm3/s = √2g × h
h = 50 mm
At down, V2 = √2g(200 50) = 2236.06 mm/s
A2V2 = 6.5 × 105
∴ A2 = 290.68 mm2
