science in three

 Prefix: K, Kilo- = 1000 = 103.


Three laws of motion by Sir Isaac Newton (1687). The 1st law: An object will remain at constant velocity unless a non-zero force acts upon it. The 2nd law: The force will accelerate an object in the direction of that force; the acceleration is proportional to the force and inversely proportional to the object’s mass. The 3rd law: For every force, there is an equal and opposite force.


Three thermodynamics laws. The 1st law: Energy cannot be created or destroyed, but only converted from one form to another. The 2nd law: Heat cannot of itself pass from a colder to a warmer body. The 3rd law: The entropy of ordered solids reaches zero at the absolute zero of temperature.


Three Kepler’s laws on planets’ orbital movement around the Sun. The 1st law: Each planet’s orbit is an ellipse with the Sun at one focus. The 2nd law: The rate of area that swept by a planet along its orbit is constant. The 3rd law: The ratio of the semi-major axis to the square of the period is constant for all the planets.


The well-known “three-body problem” in mathematical physics, studied by many mathematicians D’Alembert, Leonhard Euler, Joseph-Louis Lagrange, Jacobi and Laplace…


3-dimensional (3D or 3-D) figure has length, width and height/depth (or 3 coordinates).


The number of means of heat transfer: heat connection, heat conduction and heat convection.


The number of different classifications of rock: igneous, metamorphic (or pyroclastic) and sedimentary.


The triple point of water is the thermodynamic temperature at which water forms an interface of 3 phases: solid, liquid and vapor: 0.01 oC (Celsius or centigrade) = 273.16 K (Kelvin) = 32.018 oF (Fahrenheit).


Frequency Ranges





3 Hz –

300 Hz

Extremely Low Frequency (ELF)


300 Hz –

3 KHz

Voice Frequency (VF)

Telephone Circuitry

3 KHz –

30 KHz

Very Low Frequency (VLF)

High Fidelity

30 KHz- 300 KHz

Low Frequency (LF)

Maritime Mobile

300 KHz –

3 MHz

Medium Frequency (MF)

Navigational Radio, Land-maritime Mobile

3 MHz –

30 MHz

High Frequency (HF)

Maritime, Aeronautical, Amateur Radio

30 MHz –

300 MHz

Very High Frequency (VHF)

Maritime, Meteorological Communication, Television

300MHz –

3 GHz

Ultra High Frequency (UHF)

Television, Military, Low Range Radar

3 GHz –

30 GHz

Super High Frequency (SHF)

Space, Satellite, Microwave

30 GHz –

300 GHz

Extremely High Frequency (EHF)

Radio Astronomy




Leave a Reply