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#ejection speed

10 public questions tagged with this topic.

A spray tube (7cm2) has 35 holes of diameter 1.2mm. If the flow speed is 3.0m/min, what is the ejection speed?

A1v1 = A2v2, v1 = 3.0m/min = 0.05m/s, A1 = 7×10−4m2. Hole area: Ah = π(0.6×10−3)2, total A2 = 35×π×3.6×10−7≈3.958×10−5m2. v2 = 7×10−4×0.053.958×10−5≈0.884m/s. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 0.9 m/s. This satisfies dimensional consistency and physical conditions given, so option C is scientifically correct.

Ref: NCERT Class 11 Physics, Thermal Properties and Gravitation.

A spray tube (10cm2) has 50 holes of diameter 0.9mm. If the flow speed is 2.5m/min, what is the ejection speed?

A1v1 = A2v2, v1 = 2.5m/min = 0.04167m/s, A1 = 10×10−4m2. Hole area: Ah = π(0.45×10−3)2, total A2 = 50×π×2.025×10−7≈3.181×10−5m2. v2 = 10×10−4×0.041673.181×10−5≈1.31m/s. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 1.3 m/s. This satisfies dimensional consistency and physical conditions given, so option B is scientifically correct.

Ref: NCERT Class 11 Physics, Thermal Properties and Gravitation.

A spray tube (7cm2) has 35 holes of diameter 0.8mm. If the flow speed is 3.0m/min, what is the ejection speed?

A1v1 = A2v2, v1 = 3.0m/min = 0.05m/s, A1 = 7×10−4m2. Hole area: Ah = π(0.4×10−3)2, total A2 = 35×π×1.6×10−7≈1.759×10−5m2. v2 = 7×10−4×0.051.759×10−5≈1.99m/s. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 2.0 m/s. This satisfies dimensional consistency and physical conditions given, so option B is scientifically correct.

Ref: NCERT Class 11 Physics, Thermal Properties and Gravitation.

A spray tube (5cm2) has 25 holes of diameter 1.3mm. If the flow speed is 2.7m/min, what is the ejection speed?

A1v1 = A2v2, v1 = 2.7m/min = 0.045m/s, A1 = 5×10−4m2. Hole area: Ah = π(0.65×10−3)2, total A2 = 25×π×4.225×10−7≈3.318×10−5m2. v2 = 5×10−4×0.0453.318×10−5≈0.678m/s. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 0.7 m/s. This satisfies dimensional consistency and physical conditions given, so option C is scientifically correct.

Ref: NCERT Class 11 Physics, Thermal Properties and Gravitation.

A spray tube (9cm2) has 45 holes of diameter 0.6mm. If the flow speed is 2.0m/min, what is the ejection speed?

A1v1 = A2v2, v1 = 2.0m/min = 0.0333m/s, A1 = 9×10−4m2. Hole area: Ah = π(0.3×10−3)2, total A2 = 45×π×9×10−8≈1.272×10−5m2. v2 = 9×10−4×0.03331.272×10−5≈2.36m/s. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 2.4 m/s. This satisfies dimensional consistency and physical conditions given, so option C is scientifically correct.

Ref: NCERT Class 11 Physics, Thermal Properties and Gravitation.

A spray tube (4cm2) has 20 holes of diameter 1.4mm. If the flow speed is 1.8m/min, what is the ejection speed?

A1v1 = A2v2, v1 = 1.8m/min = 0.03m/s, A1 = 4×10−4m2. Hole area: Ah = π(0.7×10−3)2, total A2 = 20×π×4.9×10−7≈3.079×10−5m2. v2 = 4×10−4×0.033.079×10−5≈0.39m/s. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 0.39 m/s. This satisfies dimensional consistency and physical conditions given, so option B is scientifically correct.

Ref: NCERT Class 11 Physics, Thermal Properties and Gravitation.

A spray pump tube (10cm2) has 50 holes, each of diameter 0.8mm. If the flow speed inside is 1.2m/min, what is the ejecti

A1v1 = A2v2, v1 = 1.2m/min = 0.02m/s, A1 = 10×10−4m2. Hole area: Ah = π(0.4×10−3)2, total A2 = 50×π×1.6×10−7≈2.51×10−5m2. v2 = A1v1A2 = 10×10−4×0.022.51×10−5≈0.8m/s. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 0.8 m/s. This satisfies dimensional consistency and physical conditions given, so option B is scientifically correct.

Ref: NCERT Class 11 Physics, Thermal Properties and Gravitation.

A spray tube (5cm2) has 25 holes of diameter 1.0mm. If the flow speed is 2.4m/min, what is the ejection speed?

A1v1 = A2v2, v1 = 2.4m/min = 0.04m/s, A1 = 5×10−4m2. Hole area: Ah = π(0.5×10−3)2, total A2 = 25×π×2.5×10−7≈1.963×10−5m2. v2 = 5×10−4×0.041.963×10−5≈1.02m/s. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 1.02 m/s. This satisfies dimensional consistency and physical conditions given, so option B is scientifically correct.

Ref: NCERT Class 11 Physics, Thermal Properties and Gravitation.

A spray tube (6cm2) has 30 holes of diameter 1.2mm. If the flow speed is 1.8m/min, what is the ejection speed?

A1v1 = A2v2, v1 = 1.8m/min = 0.03m/s, A1 = 6×10−4m2. Hole area: Ah = π(0.6×10−3)2, total A2 = 30×π×3.6×10−7≈3.39×10−5m2. v2 = 6×10−4×0.033.39×10−5≈0.531m/s. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 0.53 m/s. This satisfies dimensional consistency and physical conditions given, so option B is scientifically correct.

Ref: NCERT Class 11 Physics, Thermal Properties and Gravitation.

A spray tube (6cm2) has 30 holes of diameter 1.1mm. If the flow speed is 3.6m/min, what is the ejection speed?

A1v1 = A2v2, v1 = 3.6m/min = 0.06m/s, A1 = 6×10−4m2. Hole area: Ah = π(0.55×10−3)2, total A2 = 30×π×3.025×10−7≈2.851×10−5m2. v2 = 6×10−4×0.062.851×10−5≈1.26m/s. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 1.3 m/s. This satisfies dimensional consistency and physical conditions given, so option C is scientifically correct.

Ref: NCERT Class 11 Physics, Thermal Properties and Gravitation.