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WHY FORMULA?

 

    We use formula widely in science.  All the physics phenomenon are represented by mathematical formula.  They pack lot of information in a nut shell.  They can be easily written, manipulated and easy to remember.  Also they make calculation easy.  Let us take one simple example- a three symbol formula.  
F= ma
force = mass X acceleration.

 1. When one kick a ball, the force is transfered from the leg to the ball. To carry a mechanical force a body of some mass is required.  Without a mass, force is 0.  If m= 0 then f=0.
2. When the force is increased, mass cannot increase and hence acceleration increases. That is what a accelerator does in a motor vehicle.
3. Both the mass and acceleration contribute to the force.  A light bullet with high acceleration requires large force.  A heavy truck with a little acceleration also requires a huge force.  
4. A body moving steadily with zero acceleration is under no external force.  Planets and satellites revolves steadily and hence we can say that they are not disturbed by any force.  If a=0 then f=0.
5. We know all the falling bodies have the acceleration of 9.8 m/sec^2.  Also the falling bodies accelerates continuously.  That means earth gravitational force continuously act on them - everywhere and every instant.
6. This formula is the consequence of newton's first and second law.
7. This formula can be applied to atomic particles like protons or planets like Jupiter.
8.Mechanical, gravitational, electric, magnetic and other forces obey this formula.
9. Manipulating the formula, we get m=f/a. That is, if you divide the force on the body by its acceleration, we get the mass of the body.  This is another way of measuring the mass called inertial mass. This technique is used in space to measure the mass.  Here we can conclude that the mass is the kind of "resistance" offered by the body to accelerate. 
10. A body is starting to move or coming to rest means "force is in action".  

     This formula help us to visualize invisible force.  That is why we always go for a formula to represent a concept.

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