FLUID FLOW

1.          1996 Q24 P1
State how the pressure in a moving fluid varies with the speed of the fluid (1 mark)
2.          1997 Q18 P1
Water flows in a horizontal smooth pipe. State the changes that would be observed in the nature of the flow if the speed of the water is steadily increased from low to a high value
3.          1998 Q30 P1
Fig 9 shows a Bunsen burner.

Use Bernoulli’s principle to explain how air is drawn into the burner, when, the gas tap is opened.

4.          1999 Q25 P1
Figure 13 shows a section of a pipe PQ. A constant pressure difference    maintains a streamline flow of a liquid in the pipe.

If the cross-sectional area A1 at P is less than A2 at Q, state how the liquid velocity. V2 at Q compares with velocity V1 at P.

5.          2000 Q25 P1
A student holds a sheet of paper at one end so that it hangs in the position A shown in fig. 14

Explain why the paper rises to the position B when the student blows air in the direction shown by the arrow.

 6.          2001 Q23 P1
Fig. 16 shows a non – viscous fluid flowing through a pipe a long which   vertical tubes A, B and C have been fitted.

Complete the diagram by indicating the possible levels of the fluid in tubes B and C.
 8.          2003 Q36 P1
Figure 19 shows a pith ball placed in a flask. When a jet of air is blown over the mouth of the flask as shown, the pith ball is observed to rise form the bottom

 Explain this observation

 9.          2005 Q26 P1
State Bernoulli’s principle.   (1 mark)
10.          2006 Q11 P1
A pipe of radius 6 mm is connected to another pipe of radius 9 mm. If water flows in the wider pipe at the speed of 2 ms-1, what is the speed in the narrower pipe?  (3 marks)   
11.          2007 Q3 P1
Figure 2 shows a tube of varying cross sectional area

Arrange the speed V1, V2, V3 and V4 in decreasing order starting with the highest   (1 mark)

12.          2008 Q12 P1
Fig. 6 shows a sheet of paper rolled into a tube.

When a fast stream of air is blown into the tube as shown in the diagram the paper tube collapses. Explain the observation.     (2 marks)

13.          2009 Q11 P1
Figure 6 shows two inflated ballons hanging vertically on light threads

When a stream of air is blown in the space between the balloons, they are observed to move towards each other. Explain this observation.   (1 mark)

14.          2010 Q7 P1
Figure 4 shows a horizontal tube with two vertical tubes x and y. water flows through the horizontal tube from right to left. The water level in tube x is higher than water in tube y.

Explain this observation.

15.   2012 Q14 P1
1.  An aeroplane is moving horizontally through still air at a uniform speed. It isobserved that when the speed of the plane is increased, its height above the ground increases. State the reason for this observation.   (1 mark)
(b) Figure 5 shows parts A, B and C of a glass tube.

State with a reason the part of the tube in which the pressure will be lowest when air is blown through the tube from A towards C.  (2 marks)