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141.

When the water flows over a rectangular suppressed weir the pressure beneath the nappe is

142.

The effect of negative pressure beneath the nappe in case of flow of water over a rectangular suppressed weir is to

A.	Decrease the discharge	B.	Increase the discharge
C.	Increase frictional resistance	D.	Reduced frictional resistance
E.	None of the above

143.

In order that the water shall never rise more than 100 cm above the crest for a discharge of 5 cube metres per second, the length of weir will be

144.

The hydraulic gradient line

A.	Is always below the total energy line	B.	Is always parallel to the bottom
C.	Is same as central line of section	D.	Is always above the total energy line
E.	Is always below the total energy line

145.

Force on a flat stationary plate is

A.	Velocity of jet before impact - velocity after impact	B.	Difference in velocities of jet in the direction normal to plate
C.	Mass of water x (difference in velocities of jet)	D.	Mass of striking water x (velocity before impact in the direction normal to plate-velocity fter impact in the direction normal to plate).
E.	None of the above

146.

Undershot water wheels are those on which water acts

A.	Purely by impulse	B.	Partly by impulse and partly by reaction
C.	Purely by reaction	D.	None of the above

147.

Out ward radial flow turbines

A.	Are impulse type	B.	Are reaction type
C.	Are partly impulse partly reaction	D.	May be impulse or reaction type
E.	None of the above

148.

The specific speed of a pump is defined as the speed of a pump

A.	Of unit size with unit discharge at unit head	B.	Of such size that it requires unit power for unit head
C.	Of such size that it delivers unit discharge at unit head	D.	Of such size that it delivers unit discharge at unit power
E.	None of these answers

149.

Cavitation is caused by

150.

In Red wood viscometer

A.	Absolute value of viscosity is determined	B.	Part of the head of fluid is utilised in overcoming friction
C.	The fluid discharges through orifice with negligible velocity	D.	The fluid should rapidly flow out of the orifice
E.	Comparison of viscosity is done