Welcome to your Density and Pressure(Senior Class Physics Study by Topics) NAME EMAIL PHONE NUMBER 1. A solid of weight 0.6N is totally submerged in oil and water respectively. If the upthrust in oil is 0.21N and the R.D of oil is 0.875, find the upthrust in water. O.18N 0.24N 0.6N 0.360N 2. A solid weighs 0.040N in air and 0.025N when fully immersed in a liquid of density 800kg/m³. Calculate the volume of the solid 0.000003kg/m³ 0.0000025kg/m³ 0.00002kg/m³ 0.000002kg/m³ 3. The diagram is of a faultless simple mercury barometer. Which of the following is NOT correct? the height of the column will not be the same if another liquid is used instead of mercury as the barometer is taken up a mountain, h, decreases if the tube is tilted, the vertical height of the mercury column will change a vacuum exists above the mercury in the tube the atmospheric pressure supports a column of mercury, h 4. When the temperature of a liquid is increased, its surface tension. decreases increases then decreases increases remains constant 5. Which of the following cannot be correctly explained using the concept of surface tension? floating of balloon in the air formation of spherical droplets when water drips from a tap formation of soap bubbles crawling of insects on the surface of a pond 6. Which of the following statements about liquid pressure is NOT correct? The pressure at any point in a liquid is the same at the same level at a point in a liquid is proportional to the depth of a liquid at any point on the wall of its container acts in all directions perpendicular to the wall is exerted equally in all directions at any point at a particular depth depends on the shape of the vessel 7. In an experiment using the relative density bottle, the following results were recorded.Mass of an empty bottle + stopper = 50gMass of a bottle full of water + stopper = 80gMass of bottle full of liquid Q + stopper = 74gUse these results to calculate the relative density of liquid Q 1.25 0.80 0.60 1.60 0.93 8. A hose ejects water at a speed of 15cm/s through a hole of area 75cm². If the water strikes a wall normally, calculate the force on the wall. (Assuming that the velocity of water after striking the wall is zero and density of water = 1000kg/m³). 0.676N 0.507N 0.169N 0.338N 9. An object of volume 1m³ and mass 2kg is totally immersed in a fluid of density 1kg/m³. Calculate its apparent weight 1N 20N 10N 2N 10. A pilot records the atmospheric pressure outside the plane as 63cm of Hg while a ground observer records a reading of 75cmHg for the atmospheric pressure on the ground. Assuming that the density of the atmosphere is constant, calculate the height of the plane above the ground. (Relative density of Hg = 13.0 and of the air = 0.00013). 12,000m 7,500m 13,800m 6,300m 11. The diagram below shows 3 identical blocks of wood floating in liquids P, Q & R. Which of the following statements is correct? the blocks will sink more as the temperatures of the liquids fall the upthrust on each block is the same the upthrust increases as the temperatures of the liquids fall the volumes of the blocks below the liquid surface are the same the upthrust decreases as the temperatures of the liquids fall 12. The terminal velocity of a ball-bearing falling through a viscous fluid is reached when the upthrust is equal to the velocity of the ball ball accelerates uniformly velocity is uniform upthrust is equal to the weight of the ball 13. An empty 60L petrol tank has a mass of 10kg. Its mass when full of fuel of relative density 0.72 is 7.2kg 33.2kg 43.2kg 53.2kg 14. Calculate the pressure on Radeyah's thumb when she exerts a force of 20N and the top of the pin is square, the length of each side being 10mm0.2N/mm² 12N/mm² 0.2N/mm² 2N/mm² 20N/mm² 15. The instrument used for measuring atmospheric pressure is manometer hydrometer photometer ratemeter barometer 16. What is the height of the liquid column in a barometer tube that would support an atmospheric pressure of 102,000N/m² if the density of the liquid is 2,500kg/m³. (g = 10m/s²). 39.23m 3.92m 0.75m 0.76m 17. Mercury forms little balls when it is spilled on a bench because it has a high surface tension has a high density is very viscous is a liquid metal adheres to the bench 18. A man on a bench will exert the greatest pressure on the bench when he lies flat on his belly Stands on the toes of one foot lies flat on his back Stands on one foot only stands on both feet 19. Which of the following is obeyed if a force on a sphere moving through a viscous fluid is proportional to its speed, radius and viscosity? Pascal's principle Stoke's law Bernoulli's law Archimedes' principle 20. An object of mass 400g and density 600kg/m³ is suspended with a string so that half of it is immersed in paraffin of density 900kg/m³. The tension in the string is 4N 1N 5N 3N 21. A weightless vessel of dimensions 4m x 3m x 2m is filled with a liquid of density 1000kg/m³ and sealed. What is the maximum pressure this container can exert on a flat surface? 30,000N/m² 20,000N/m² 40,000N/m² 90,000N/m² 22. When a paint brush is removed from clean water, the bristles of the brush are pulled together because of surface tension the mass of the brush bristles low density of water the weight of the brush bristles the viscousity of the surrounding 23. In the diagram below, V is the viscosity, U is upthrust. Which of the following equations holds when the falling body P has attained a terminal velocity? V = mg/U V + mg + U = 0 V + U - mg = 0 V - U = mg V + mg = U 24. A hose of cross- sectional area 0.5m² is used to discharge water from a water tanker at a velocity of 60m/s in 20s into a container. If the container is filled completely, the volume of the container is 600m³ 2400m³ 6000m³ 240m³ 25. The density of water is 1g/cm³ while that of ice is 0.9g/cm³. Calculate the change in volume when 90g of ice is completely melted. 9cm³ 10cm³ 90cm³ 100cm³ 0cm³ 1 out of 25 Time is Up! Time's up