 ## PCM से 12th करने के बाद कौन सा course करें

आज इस Blog में हम बात करेंगे की अगर आप 12th PCM ( Physics , Chemistry , Mathematics ) से कर रहे हैं तो 12th के बाद क्या क्या Opportunities आपके होगी और कौन सा course कर के आप अच्छा Career बना सकते हैं

## JEE Mains के लिए Physics की best Books

JEE Mains के लिए Physics की best Books
1. NCERT PHYSICS
2. Concept of physics
3. Understanding physics
4. Physics – B.M Sharma
5. Previous Year

## Gravitational Self energy of a Uniform hollow and solid sphere – Definition and Derivation .

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

## Gravitational field and field strength | Definition , formula , Derivation and solved examples

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 ## Torricelli’s theorem ( Velocity of efflux ) : Principle , Derivation and sloved examples

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 ) .

## Force of reaction due to ejection of liquid – Derivation, Equation and Solved examples

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 . ## Newton’s law of Universal Gravitation | Definition , Equation , Facts and Solved Examples.

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.