## NEWTON´S LAWS

1-. The Inercia law : An object at rest remains at rest, or if in motion, remains in motion at a constant velocity unless acted on by a net external force. What Newton states is that an acceleration is the result of applying a force to the object. 2-. Newton’s second law of motion pertains to the behavior of objects for which all existing forces are not balanced. The second law states that the acceleration of an object is dependent upon two variables – the net force acting upon the object and the mass of the object. The acceleration of an object depends directly upon the net force acting upon the object, and inversely upon the mass of the object. As the force acting upon an object is increased, the acceleration of the object is increased. As the mass of an object is increased, the acceleration of the object is decreased. 3-.  For every action, there is an equal and opposite reaction. The statement means that in every interaction, there is a pair of forces acting on the two interacting objects. The size of the forces on the first object equals the size of the force on the second object. The direction of the force on the first object is opposite to the direction of the force on the second object. Forces always come in pairs – equal and opposite action-reaction force pairs.

## HYDROSTATICS EQUATION

Hydrostatic equation is an elegant way to explain  the effect that happens when we are drinking with a straw.

### ¿ What happens while drinking with a straw? The preassure at the bottom of the glass is higher that the pressure we are producing with the mouth. Resulting in an upwards movement of the fluid.

Once the fluid is on the straw and we cover the side in contact to the mouth, we can observe that the fluid is not moving.

In Conclusion,The fluid is moving from higher pressure to lower pressure.

## SPEED OF SOUND & MACH NUMBER

Speed of sound mainly depends  on the temperature Co it is the speed of sound at see level , in I.S.A conditions.

• MACH NUMBER (MN) it is the relationship between the true air speed and the speed of sound.

The higher we fly the lower temperature we have so the speed of sound decreases. That´s why the mach number increases. MN<0.5  The air is considered incompressible

MN<1 Subsonic

MN=1 Sonic

MN>1 Supersonic

This site uses Akismet to reduce spam. Learn how your comment data is processed.