How a raincoat become rainproof?

Can Bernoulli's equation be used to describe the flow of water through a rapid in a river? Explain.

Three vessels have same base area and different neck area. Equal volume of liquid is poured into them, which will possess more pressure at the base?

What us the use of open tube manometer?

A mercury barometer is placed in the mercury through in a way that angle mad with the vertical is \({ 60 }^{ \circ }\).Find the height of mercury column.

Viscosity of gases ... with temperature, whereas viscosity of liquids ... with temperature (increases / decreases)

The terminal velocity of a copper ball of radius 2.0 mm falling through a tank of oil at 20^oC is 6.5 cm s^-1. Compute the viscosity of the oil at 20^oC. Density of oil is 1.5 ×10³ kg m^-3, density of copper is 8.9 × 10³ kg m^-3.

What should be the average velocity of water in a tube of radius 0.005m so that the flow is just turbulent?The viscosity of water is 0.001 Pa-s.

27 identical drops of water are falling down vertically in air each with a terminal velocity 0.15\(ms^{ -1 }\)>if they combine to form a single bigger drop, what will be its terminal velocity?

Air is streaming past a horizontal air plane wing such that its speed is 120 ms lover the upper surface and 90 ms^-1 at the lower surface. If the density of air is 1.3 kgm^-3, find the difference in pressure between the top and bottom of the wing. If wing is 10 m long and has an average width of 2 m, calculate the gross lift of the wing.

The cylindrical tube of a spray pump has a cross-section of 8.0 cm² one end of which has 40 fine holes each of diameter 1.0 mm. If the liquid flow inside the tube is 1.5 m min–1, what is the speed of ejection of the liquid through the holes ?

What should be the maximum average velocity of water in a tube of diameter 0.5 cm. So that the flow is laminar? The viscosity of water is 0.00125 Nm^-2 s.

A capillary of radius 0.05 cm is immersed in water. Find the value of rise of water in capillary if value for the surface tension is 0.0073 N/m and angle of contact  is 0⁰ 

If the water emerges from the an orifice in a tank in which the gauge pressure is 4\(\times\)10⁵N.m²  before the flow starts then, what will be the velocity of the water emerging out? Take density of water is 1000 kgm^-3 .

What is the pressure inside the drop of mercury of radius 3.00mm at room temperature? Surface tension of mercury at that temperature (20⁰C) is 4.65 \(\times\) 10^-1 N/m. The atmospheric pressure is 1.01\(\times\)10⁵ Pa. Also, give the excess pressure inside the drop.

Water flows through a horizontal pipe whose internal diameter is 2.0 cm , at speed of 1.0 ms^-1 . What should be the diameter of the nozzle, if the water is to emerge at a speed of 4.0 ms^-1 ?

Explain why?
A fluid flowing out of small hole in vessel results in a backward thrust on the vessel.  According to Bernoulli's theorem, for horizontal flow of fluids,  \(\left( p+\frac { 1 }{ 2 } \rho { v }^{ 2 }=constant \right) \) Therefore, when velocity of fluid increases, its pressure decreases and vice-versa.

Mercury has an angle of contact equal to 140⁰ with soda lime glass. A narrow tube of radius 1.00 mm made of this glass is dipped in a trough containing mercury. By what amount does the mercury dip down in the tube relative to the liquid surface outside? Surface tension of mercury at the temperature of th experiment is 0.456 N/m .Density of mercury? =13.6\(\times\)10³ kg/m³