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31.

The function of guide vanes in a reaction turbine is to

A.	allow the water to enter the runner without shock	B.	allow the water to flow over them, without forming eddies
C.	allow the required quantity of water to enter the turbine	D.	all of the above

32.

In a reaction turbine, the draft tube is used

A.	to run the turbine full	B.	to prevent air to enter the turbine
C.	to increase the head of water by an amount equal to the height of the runner outlet above the tail race	D.	to transport water to downstream

33.

Which of the following statement is correct?

A.	In an impulse turbine, the water impinges on the buckets with pressure energy.	B.	In a reaction turbine, the water glides over the moving vanes with kinetic energy.
C.	In an impulse turbine, the pressure of the flowing water remains unchanged and is equal to atmospheric pressure	D.	In a reaction turbine, the pressure of the flowing water increases after gliding over the vanes.

34.

In an inward flow reaction turbine

A.	the water flows parallel to the axis of the wheel	B.	the water enters at the centre of the wheel and then flows towards the outer periphery of the wheel
C.	the water enters the wheel at the outer periphery and then flows towards the centre of the wheel	D.	the flow of water is partly radial and partly axial

35.

In an axial flow reaction turbine, the water flows

parallel

perpendicular

36.

In an outward flow reaction turbine

A.	the water flows parallel to the axis of the wheel	B.	the water enters at the centre of the wheel and then flows towards the outer periphery of the wheel
C.	the water enters the wheel at the outer periphery and then flows towards the centre of the wheel	D.	the flow of water is partly radial and partly axial

37.

In a mixed flow reaction turbine, the flow of water is partly radial and partly axial.

Correct

Incorrect

38.

The hydraulic efficiency of a reaction turbine, is the ratio of

A.	power produced by the turbine to the energy actually supplied by the turbine	B.	actual work available at the turbine to energy imparted to the wheel
C.	workdone on the wheel to the energy (or head of water) actually supplied to the turbine	D.	none of the above

39.

The ratio of actual work available at the turbine to the energy imparted to the wheel is known as

A.	hydraulic	B.	mechanical
C.	overall

40.

A Francis turbine is an outward flow reaction turbine.

True

False