height of water at that point. 6. An open tank contains water upto a depth of 1.5 m and above it an oil of sp. gr. 0.8 for a depth of 2 m.F the pressure intensity : (#) at the interface of the two liquids, and (i) at the bottom of the tank. (Ans. () 1.57 N/em', (i) 3.04 Niem 7. The diameters of a small piston and a large piston of a hydraulic jack are 2 cm and 10 cm respectively, A force of 60 N is applied on the small piston. Find the load lifted by the large piston, when : (a) the pistons at the same level, and (b) small piston is 20 cm above the large piston. The density of the liquid in the jack [Ans. (a) 1500 N, (b) 15205 N] kg given as 1000 m 8. Determine the gange and absolute pressure at a point which is 2.0 m below the free surface of water. Take [Ans. 1.962 N/em? (gauge), 12.066 N/em (abx.)] atmospheric pressure as 10.1043 Nicm. 9. A simple manometer is used to measure the pressure of oil (sp. gr. = 0.8) flowing in a pipe line. Its right limb is open to the atmosphere and left limb is connected to the pipe. The centre of the pipe is 9 cm below the level of mercury (sp. gr. 13.6) in the right limb. If the difference of mercury level in the two limbs is 15 [Ans. 12.058 Nem'] 10. A simple manometer (U-tube) containing mercury is connected to a pipe in which an oil of sp. gr. 0.8 is flowing. The pressure in the pipe is vacuum. The other end of the manometer is open to the atmosphere. Find the vacuum, pressure in pipe, if the difference of mercury level in the two limbs is 20 cm and height [Ans. - 27.86 Nem) 11. A single column vertical manometer (Le, microimcter) is connected to a pipe containing oil of sp gr.0.9 The area of the reservoir is 80 times the area of the manometer tube. The reservoir contains mercury sp. gr. 13.6. The level of mercury in the reservoir is at a height of 30 cm below the centre of the pipe a difference of merçury levels in the reservoir and right limb is 50 cm. Find the pressure in the pipe (Ans. 6.474 Nkm] 12. A pipe contains an oil of sp. gr. 0.8. A differential manometer connected at the two points A and B of the pipe shows a difference in mercury level as 20 cm. Find the difference of pressure at the two points (Ans. 25113.6 Nim) 13. A U-tube differential manometer connects two pressure pipes A and B. Pipe A contains carbon tetrachloride having a specific gravity 1.594 under a pressure of 11.772 N/cm² and pipe B contains ol sp. gr. 0.8 under a pressure of 11.772 N/em. The pipe A lies 2.5 m above pipe B. Find the difference of [Ans. 31.36 cm of mercury] 14. A differential manometer is connected at the two points A and B as shown in Fig. 2.25. At B air pressue cm, determine the absolute pressure of the oil in the pipe in N/cm². of oil in the left limb from the centre of the pipe is 15 cm below. pressure measured by mercury as fluid filling U-tube. is 7.848 N/em (abs.), find the absolute pressure at A. (Ans. 6.91 Nem) AIR WATER OIL Sp. gr.0.8 OIL Sp. gr. 0.8 王 50'cm 30'cm 100 am 50 cm MERCURY Sp. g.13.0 WATER Fig. 2.25 Fig. 2.26