The stylus of a phonograph record exerts a force of 4 x 10-2N/m2 on a groove of radius 10-2m. Compute the pressure exerted by the stylus on the groove.
A cube of glass of 5cm side and mass 306g has a cavity inside it. If the density of glass is 2.55g/cm³, what is the volume of the cavity?
If the relative density of a metal is 19. What will be the mass of 20cm³ of the metal when immersed in water?
A well 1km deep is filled with a liquid of density 950kg/m³. If the atmospheric pressure is 100000N/m² and g = 10m/s², the pressure at the bottom of the well is
The density of 400cm³ of oil was 0.9g/cm³ before frying. If the density of the oil was 0.6g/cm³ after frying, assuming no loss of oil due to spilling, its new volume was
Why does a piece of cork float on water?
Which of the following factors influence the rate of flow of water through a pipe to houses?
I. the material of the pipe
II. the diameter of the pipe
III. the viscosity of the water
A rectangular tank contains water to the depth of 2m. If the base is 4m x 3m, calculate the force on the base ( density of water = 1000kg/m³, g = 10m/s²)
Which of these statements are true of pressure in liquid?
I. pressure acts equally in all directions
II. pressure decreases with depth
III. pressure at the same level of a liquid is the same
IV. pressure is dependent on the cross-section area of the barometer tube
What is the total pressure in cmHg at a point 15m below the surface of a fresh water reservoir. Atmospheric pressure, 76cmHg, density of mercury is 13.6g/cm³
Mercury is a better barometric fluid than water because
I. it needs no colouring
II. its density is many times greater than that of water
III. it does not wet glass
IV. it has a high boiling point.
Which of the following is suitable to use an altimeter?
The instrument used for measuring atmospheric pressure is
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
Two divers G & H are at depths 20m & 40m respectively below the water surface in a lake. The pressure on G is P1 while the pressure on H is P2 . If the atmospheric pressure is equivalent to 10m of water, the value of P2 /P1 is
Mercury forms little balls when it is spilled on a bench because it
A balloon filled with hydrogen rises when released into the air because
The pressure at any point in a liquid at rest depends only on the
A uniform cylindrical block of wood floats in water with one-third of its length above the water level. In a liquid of R.D 0.8, what fraction of its height would be above the liquid level?
If a fluid flows out of a narrow tube at a depth h below the surface, its velocity is
When a ship sails from salt water into fresh water, the fraxction of its volume above the water surface will?
IV. nature of substance
Which of the above affects diffusion?
A cube of side 10cm and mass 0.5kg floats in a liquid with only one-fifth of its height above the surface of the liquid. What is the R.D of the liquid?