1. Air is blown through a pipe AB at a rate of 15 litre per minute. The cross-sectional area of broad

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1 Keshaw Classes IIT/JEE Medical Classes 5-A / 9, WEA, Sat Nagar, Karol Bagh New Delhi Mob: , Ph: keshawclasses@gmail.com Web: Solids and Fluids 1. Air is blown through a pipe AB at a rate of 15 litre per minute. The cross-sectional area of broad Portion of pipe AB is 2 cm 2 and of the narrow portion and of tube abc is 0.5 cm 2. The difference Δh between the levels of water poured into the tube abc is (The density of air is 1.32 kg/m3.) A B Δh c a b (a) 0.8 mm (b) 1.6 mm (c) 2.4 mm (d) 3.2 mm 2. The deformation of a wire under its own weight compared to the deformation of same wire Subjected to a load equal to the weight of the wire is (a) same (b) one third (c) half (d) one fourth 3. A cubical tank of edge 60 cm is filled with water to a height of 30 cm and oil of specific gravity 0.8 to A further height of 30 cm. the thrust at the bottom is (a) 1905 N (b) 450 N (c) 900 N (d) 3810 N

2 4. The diameter of a pipe at the entrance and exit being 10 cm and 7.5 cm and pressure drop across its Length is 25 cm of mercury column. The velocity of flow of water at the two ends of a conical section Of a pipe placed horizontally are respectively (Given ρ Hg = 13.6 gm/cc) (a) 9.87 m/s, 5.55 m/s (c) 0.98 m/s, 0.55 m/s (b) 98.7 m/s, 55.5 m/s (d) 4.9 m/s, 2.75 m/s 5. A rectangular block of wood measuring 3 m 1 m of relative density 0.75 floats in water with its long axis horizontal and four faces vertical. The work done in lifting the block vertically out of water is (a) 8269 J (b) J (c) 4134 J (d) J 6. A gas having density ρ flows with a velocity v along a pipe of cross sectional area s and bent at an Angle of 90 0 at a point A. the force exerted by the gas on the pipe at A is (a) (b) sv 2 ρ (c) sv 2 ρ (d) sv 2 ρ 2 7. A tank is filled what water and an orifice is made in the wall so that the horizontal range x of water Rushing out is maximum. If H is the height of water above the orifice in the tank, then (a) x = H (b) x = 2H (c) 2x = H (d) 4x H 8. The height of a mercury barometer is 75 cm at sea level and 50 cm at the top of a hill. Ratio of density of mercury to that of air is10 4. The height of the hill is (a) 250 m (b) 2.5 km (c) 1.25 km (d) 750 m 9. An ornament weighing 50 g in air, weighs only 47 g in water due to mixing of copper with gold to Prepare the ornament. The amount of copper in the ornament is (specific gravity of gold is 20 and that of copper is 10) (a) 16 g (b) 12 g (c) 10 g (d) 20 g 10. The specific gravity of ice is 0.9. the area of the smallest slab of ice of height 0.5 m floating in fresh Water that will just support a 100 kg man is (a) 1.5 m 2 (b) 2 m 2 (c) 3 m 2 4 m 2

3 11. When a 60 N stone is attached to a scale and submerged in water, the scale reads 40 N. the volume Of the stone is (a) 2.04 m 3 (b) m 3 (c) m 3 (d) 1.02 m A solid uniform ball having volume V and density ρ floats at the interface of two immiscible liquids As shown in figure. The densities of the upper and the lower liquids are ρ 1 and ρ 2 respectively, Such that ρ 1 < ρ < ρ 2. The fraction of the volume of the ball in the lower liquid is (a) ρ - ρ 2 (b) ρ 1 (c) ρ 1 ρ (d) ρ 1 - ρ 2 ρ 1 - ρ 2 ρ 1 - ρ 2 ρ 1 - ρ 2 ρ It is desired to design an airplane with a lift of 1000 N per square metre of wing area. If the Velocity of streamline flow past the lower wing surface is 100 m/s, the required velocity over The upper surface (Density of air = 1.3 kg/m 3.) is nearly (a) 50 m/s (b) 100 m/s (c) 107 m/s (d) 51 m/s 14. A copper wire of negligible mass, 1 m length and cross sectional area 10-6 m 2 is kept on a smooth horizontal table with one end fixed. A ball of mass 1 kg is attached to the other end. The wire and The ball are rotating with an angular velocity of 20 rad/s. if the elongation in the wire is 10-3 m, The young s modulus is (a) 10 5 N/m 2 (b) N/m 3 (c) N/m 2 (d) N/m The breaking stress of a wire depends on (a) material of the wire radius of the wire (c) radius of the wire (b) length of the wire (d) none of these 16. A wire can be broken by applying a load of 20 kg wt. the force required to break the wire of Twice the diameter is (a) 20 kg wt (b) 5 kg wt (c) 80 kg wt (d) 160 kg wt

4 17. To get the maximum flight, a ball must be thrown as (a) (b) V v (c) (d) any one of (a), (b) and (c) 18. The weight of a body in water is one third of its weight in air. The density of the body is (a) 0.5 gm/cm 3 (b) 1.5 gm/ cm 3 (c) 2.5 gm/ cm 3 (d) 3.5 gm/ cm A barometer kept in an elevator accelerating upward reads 76 cm. the air pressure in the Elevator is (a) 76 cm (b) < 76 cm (c) > 76 cm (d) zero 20. The three vessels shown in the figure have exactly the same base area. Equal volumes of a Liquid are poured in the three vessels. The force on the base will be (A) (B) (C) (a) maximum in vessel A (c) maximum in vessel C (b) maximum in vessel B (d) equal in all the vessels 21. A water tank is 20 m deep. If the water barometer reads 10 m, pressure at the bottom of the tank is (a) 2 atmosphere (b) 1 atmosphere (c) 3 atmosphere (d) 4 atmosphere

5 22. Equal volumes of water and alcohol are mixed together. The density of water is 1000 kg/m 3 and the Density of alcohol is 800 kg/m 3. The density of the mixture is (a) 900 kg/m 3 (b) 1100 kg/m 3 (c) 875 kg/m 3 (d) 950 kg/m A body of mass 0.5 kg is attached to a thread and it just floats in a liquid. The tension in the thread is (a) 0.5 kg wt (c) less than 0.5 kg wt (b) more than 0.5 kg wt (d) zero 24. The volume of a liquid flowing per sec out of an orifice at the bottom of a tank does not depend Upon (a) the height of the liquid above the orifice (b) the acceleration due to gravity (c) the density of the liquid (d) the area of the orifice 25. Two large tanks, open at the top, contain different liquids. A small hole is made in the side of each tank at the same depth h below the liquid surface but one hole is twice the cross- sectional area Of the other. The ratio of densities of liquids so that the mass of flux is same for each hole is (a) 4 (b) 3 (c) 2 (d) A wire can sustain a weight 20 kg before breaking. If the wire is cut into two equal parts, each part Can sustain a weight of (a) 10 kg (b) 20 kg (c) 40 kg (d) 80 kg 27. The weight of a body in air is 100 N. its weight in water, if it displaces 400 cc of water is (a) 90 N (b) 94 N (c) 98 N (d) None of these 28. There is a small hole at the bottom of a large open vessel. If water is filled up to a height h, velocity Of water coming out of hole is v. then velocity of water coming out of hole when water is filled to A height 4h is (a) 4 v (b) 3 v (c) 2 v (d) v

6 29. A liquid stands at and same level in the U-tube when at rest. If area of cross section of both the Limbs are equal, the difference in heights h of the liquid in the two limbs of U-tube, when the System is given an acceleration a in horizontal direction as shown is (a) gl 2 ah (b) La g (c) L 2 a (d) Hg a H g a H L 30. Water and mercury are filled in two cylindrical vessels up to same height. Both vessels have a hole in the wall near the bottom. The velocity of water and mercury coming out of the holes are V 1 and v 2 respectively. Then (a) v 1 = v 2 (b) v 1 = 13.6v 2 (c) v 1 = v 2 (d) v 1 = 13.6v

. In an elevator accelerating upward (A) both the elevator accelerating upward (B) the first is equations are valid

. In an elevator accelerating upward (A) both the elevator accelerating upward (B) the first is equations are valid IIT JEE Achiever 2014 Ist Year Physics-2: Worksheet-1 Date: 2014-06-26 Hydrostatics 1. A liquid can easily change its shape but a solid cannot because (A) the density of a liquid is smaller than that of