## Physics short question

1.Hot air rises up.Why is it cooler at the top of the a mountain than near sea level?
Ans: Hot air are lighter which rises upward when they reach at the top of mountain.Then air pressure decreases because of altitude.According to Charle’s law,at constant volume,the temperature also decreases with decreasing pressure.

## Albert Einstein

Albert Einstein is great scientist of world who born German.He is also called Father of Morden physics.His great and most important theory is “Theory Of Relativity”. This Theory explained about how time and distance may change due to the “relative” or different speed of the object and the observer.One equation from the theory is E=mc^2.In this formula,”c”is the speed of light and is a constant.This formula explained how energy (E) is related to mass(m).

Albert Einstein was awarded the Nobel prize for physics in 1921 He also wrote many paper to explain quantum physics.

## Thermodynamics process

There are following thermodynamics process.

1.Isothermal process:

The process at which pressure and volume change at constant temperature is isothermal process.It slow process.

2.Adiabatic process:

In this pressure ,volume and temperature change at constant amount of heat.

3.Isobaric process:

In this process , volume and temperature change at constant pressure.

4.Isochoric process:

In this process, pressure and temperature change at constant volume.

## Surface Tension

Surface tension is property of liquid which behaves as stretched Membrane .It is also force per unit area of line drawing on liquid Surface.It is denoted by “T”

Surface Tension,T =F/A

Where F = Force

A=Surface area