Mechanical Prop...

The terminal velocity of solid sphere of radius $$0.1$$ m moving in air in vertically downward direction, is: $$(\eta =1.8\times 10^{-5} Ns/m^2$$, density of sphere $$=1000 kg/m^3$$ and $$g=10 m/s^2$$)

How many cylinders of hydrogen at atmospheric pressure are require to fill a balloon whose volume is $$500\ m^3$$, if hydrogen is stored in cylinder of volume $$0.05\ m^3$$ at an absolute pressure of $$15\times 10^5 \ Pa$$?

A solid sphere falls with a terminal velocity of $$20m/s^{-1}$$ in air. If it is allowed to fall in vacuum 

In a steady incompressible flow of a liquid.

At $$20^o$$C, to attain the terminal velocity how fast will an aluminium sphere of radii $$1$$ mm fall through water? [Assume flow to be laminar flow and specific gravity $$(Al)=2.7$$, $$\eta_{water}=8\times 10^{-4}$$Pa]

A hole is made at the bottom of a tank filled with water $$\left(density={10}^{3}kg/m^{3}\right)$$. If the total pressure at the bottom of the the tank is $$3atm\left(1atm=10^{5}{N/m}^{2}\right)$$, then the velocity of efflux is

A tube $$1\ cm^2$$ in cross-section is attached to the top of a vessel $$1\ cm$$ high and cross- section $$100\ cm^2$$. Water fills the system upto a height of $$100\ cm$$ from the bottom of the vessel. The force exerted by the liquid at the bottom of the vessel is : 

A block of wood is floating in water in a closed vessel as shown in the figure. The vessel is connected to an air pump. When more air is pushed into the vessel, the block of wood floats with (neglect compressibility of water)

For a fluid which is flowing steadily, the level in the vertical tubes is best represented by:

Find the force acting at the pivoted end of the rod in terms of mass $$m$$ of the rod.