155. Maximum efficiency of transmission of power through a pipe, is

A.25%

B.33.30%

C.50%

D. 66.67%.

156. If the pressure at the inlet of a pipe is 90 kg/cm2 and pressure drop over the pipe line is 10 kg/cm2, the efficiency of transmission, is

A.66.60%

B.77.70%

C.55.50%

D. 88.8%.

157. For maximum horse power of a n, zzle, the head supplied must be equal to

A. head loss in the pipe due to friction

B. twice the head loss in the pipe due to friction

C. thrice the head loss in the pipe due to friction

D. four times the head loss in the pipe due to friction.

158. Hydraulic gradient is equal to

A. difference in water surfaces total length of the channel head loss due to friction

B. total length of the channel wetted perimeter

C. total length of the channel area of the cross-section

D. total length of the channel

159. The ratio of the hydraulic radius of a pipe running full to the hydraulic radius of a square section of a channel whose side is equal to the diameter of the pipe, is

A.1

B.2

C.3

D.4

160. For uniform flow in canals

A. there is a balance between the frictional loss and drop in elevation of the channel

B. bed and free water surfaces of a channel are parallel to each other

C. bed of channel represents the hydraulic gradient

D. all the above.

161. When a valve of a rigid and non-elastic pipe, carrying water whose Bulk Modulus is k and mass density is p is closed suddenly, the rise of pressure P due to water hammer, is

A. P = k p

B. P = Nrk- p

C. P = Inrp-

D. P =

Page **23** of **61**