A King (The President of Nation) may rule the Country People with energy sources available on their mother land. Humans can survive (live) on planet Earth by using the energy available here – those are Light, sound, Heat, Chemical, Mechanical, Electricity, Magnetism, Tides, Wind, Nuclear, Geothermal—–.
These energies can available in material bodies like Solids, Liquids, Gases.
Physics may explain how the material body can exhibits(transforms) above said energies in specific conditions like KING.
Example: 1) Solid – Coal(chemical) – having heat energy
2)Liquid – water — having Tidal energy
3)Gas – Thunder – having wind and electrical energy…
“So that , Physics is the branch of science that deals the relation between matter and energy”
In this way of approach (understanding of nature) , our scientists from ancient times have found three remarkable Physical Quantities for any matter , those are named as mass, length, time..
There is a first fundamental law in physics named as Homogeneity Principle:
According to this ” All the terms in any physical equation must have same units and dimensions. Mathematically we can say this as — We can Add(+) and Subtract(-) when only both the terms corresponds to same type of quantities.
example: 1) 3 kg + 5kg = 8kg —- valid, 3 kg + 5 seconds = no answer (not valid)
2) Final velocity of a ball is V = U + at , here U-initial velocity, at – extra velocity due to acceleration getting in few seconds(t).
Note: here the term means —- product or division of numbers and variables and functions…..
