Water is flowing in streamline motion through a tube with its axis horizontal. Consider two points A and B in the tube at the same horizontal level.

The pressure is dependent on the height of the fluid above the point. If the height above A is less as compared to B or vice versa, the pressures will be different.


Option (A) is not true. However, if the tube is identical at both points, their pressure will be equal. So option (B) is false.


If the tube is identical at both points, their cross-sections are equal. Hence, the pressures will be equal. Option (C) is correct. Even if the cross-sections are non-uniform, the volumes entering and exiting can be equal for different shapes. In such cases, the pressure would also be equal. Hence option (D) is correct.

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