## Artificial Satellites – an overview

So basically we can say , A satellite is a body which is constantly revolving in an orbit around a comparatively much larger body . Artificial satellite are man mad while natural satellite are made by nature

So basically we can say , A satellite is a body which is constantly revolving in an orbit around a comparatively much larger body . Artificial satellite are man mad while natural satellite are made by nature

It is the energy possessed by a body due to the interaction forces inside the body . This can be defined as the work done by external agent in assembling all the particles of a body in a definite shape and size or it is the work done in creating a body.

– gravitational self energy of a hollow sphere of mass M and radius R is given as

Uself = – GM²/2R

– gravitational self energy of the solid sphere of mass M and radius R is given as

Uself = – 3GM²/5R

Basically ” The force experienced ( both in magnitude and direction ) by a unit test mass placed at a point in a gravitational field is called the gravitational field strength or intensity of gravitational field at that point , Thus ,

E=F/m

According to Torricelli’s theorem -The velocity of efflux of a liquid issuing out of an orifice is the same as it would attain if allowed to fall freely through the vertical height between the liquid surface and orifice .

velocity of efflux v = ( 2gh )1/2

Note – The velocity of efflux is the velocity of escaping liquid relative to the container (but not necessarily relative to ground when the container moves ) .

If the velocity of a liquid (or gas) of density p coming out through an opening of area of cross section a is v, then there will be a thrust force F = ρav² due to liquid coming out the opening. The direction of the thrust force will be just opposite to the velocity direction .

The acceleration produced in the body due to gravity is called the acceleration due to gravity. It is denoted by g . Its value close to the earth’s surface is 9.8 m/s².

g = F/m = GM/R²

The magnitude of the gravitational force F that two particles of masses m1 and m2 , separated by a distance r , there exists an attraction , which is proportional to the product of their masses and inversely proportional to the square of distance between the exert force on each other is given by

F = Gm1m2 / r²

Where G is a constant , Called the universal gravitation constant . It’s value in SI units is G = 6.674×10-11 N.m²/kg².

There are various applications of Bernoulli’s Equation ( Theorem ) – pitot tube , Atomizer , siphon tube , lifting of aircraft, Blowing off the roof during wind storm , Venturimeter , Magnus effect , Velocity of efflux etc .

According to Bernoulli’s theorem, the sum total of these three kinds of energies, kinetic energy, potential energy and pressure energy remains constant along a streamline in a steady flow of an ideal fluid. That is

P + ρv²/2 + ρgh = constant

Johannes Kepler used empirical observations, and sophisticated calculations to arrive at the famous Kepler’s laws of planetary motion, published in 1609 and 1619. What is particularly significant about Kepler’s laws is that they challenged the prevailing world’s view, with the Earth in the center of the universe (a geocentric theory) and the Sun and all the planets and stars orbiting around it, just as the Moon does .