Tuesday, January 6, 2015

Physics in English



BASIC THEORY OF PHYSICS
Physics is the scientific study of matter and energy and how they interact with each other. This energy can take the form of motion, light, electricity, radiation, gravity. Just about anything, honestly. Physics deals with matter on scales ranging from sub-atomic particles (i.e. the particles that make up the atom and the particles that make up those particles) to stars and even entire galaxies.
Physics works as an experimental science, physics utilizes the scientific method to formulate and test hypotheses that are based on observation of the natural world. The goal of physics is to use the results of these experiments to formulate scientific laws, usually expressed in the language of mathematics, which can then be used to predict other phenomena.
The Role of Physics in Science
In a broader sense, physics can be seen as the most fundamental of the natural sciences. Chemistry, for example, can be viewed as a complex application of physics, as it focuses on the interaction of energy and matter in chemical systems. We also know that biology is, at its heart, an application of chemical properties in living things, which means that it is also, ultimately, ruled by the physical laws.
Major Concepts in Physics
Because physics covers so much area, it is divided into several specific fields of study , such as electronics, quantum physics, astronomy, and biophysics
About Physical Laws:
Over the years, one thing scientists have discovered is that nature is generally more complex than we give it credit for. The following laws of physics are considered fundamental, but many of them refer to idealized, closed systems, which are hard to obtain in the real world. Also, some are altered slightly in different circumstances. The laws that Newton developed, for example, are modified by the findings of the theory of relativity, but they are still basically valid in most regular cases that you'll run into.
Newton's Three Laws of Motion:
Sir Isaac Newton developed the Three Laws of Motion, which describe basic rules about how the motion of physical objects change. Newton was able to define the fundamental relationship between the acceleration of an object and the total forces acting upon it.
"Law" of Gravity:
Newton developed his "Law of Gravity" to explain the attractive force between a pair of masses. In the twentieth century, it became clear that this is not the whole story, as
Einstein's theory of general relativity has provided a more comprehensive explanation for the phenomenon of gravity. Still, Newton's law of gravity is an accurate low-energy approximation that works for most of the cases that you'll explore in physics.
Conservation of Mass-Energy:
The total energy in a closed or isolated system is constant, no matter what happens. Another law stated that the mass in an isolated system is constant. When Einstein discovered the relationship E=mc2 (in other words that mass was a manifestation of energy) the law was said to refer to the conservation of mass-energy. The total of both mass and energy is retained, although some may change forms. The ultimate example of this is a nuclear explosion, where mass transforms into energy.
Conservation of Momentum:
The total momentum in a closed or isolated system remains constant. An alternative of this is the law of conservation of angular momentum.
Laws of Thermodynamics:
The laws of thermodynamics are actually specific manifestations of the law of conservation of mass-energy as it relates to thermodynamic processes.
The zeroeth law of thermodynamics makes the notion of temperature possible.
The first law of thermodynamics demonstrates the relationship between internal energy, added heat, and work within a system.
The second law of thermodynamics relates to the natural flow of heat within a closed system.
The third law of thermodynamics states that it is impossible to create a thermodynamic process which is perfectly efficient.
Electrostatic Laws:
Coulomb's law and Gauss's law are formulations of the relationship between electrically charged particles to create electrostatic force and electrostatic fields. The formulas, it turns out, parallel the laws of universal gravitation in structure. There also exist similar laws relating to magnetism and electromagnetism as a whole.
Invariance of the Speed of Light:
Einstein's major insight, which led him to the Theory of Relativity, was the realization that the speed of light in a vacuum is constant and is not measured differently for observers in different inertial frames of reference, unlike all other forms of motion. Some theoretical physicists have conjectured different variable speed of light (VSL) possibilities, but these are highly speculative. Most physicists believe that Einstein was right and the speed of light is constant.
Modern Physics & Physical Laws:
In the realm of relativity and quantum mechanics, scientists have found that these laws still apply, although their interpretation requires some refinement to be applied, resulting in fields such as quantum electronics and quantum gravity. Care should be taken in applying them in these situations.


Base Quantities are those quantities on the basis which other quantities can be expressed.
Base Quantities
SI Unit Name
SI Unit Symbol
Length
Meter
M
Mass
Kilogram
kg
Time
Second
S
Temperature
Kelvin
K
Amount of substance
mole
mole
Electric current
ampere
A
Luminous intensity
candela
cd

Derived quantities are defined of the seven base quantities via a system of quantity equations.
Derived Quantities
SI Unit Name
SI Unit Symbol
Area
Square meter
m²
Mass density
Kilogram per cubic meter
Kg/m³
Volume
Cubic meter
m³
Speed
Meter per second
m/s²
Force
Newton
N  (kg. m/s²)
Work & Energy
Joule
J (kg. m²/ s²)
Power
Watt
W (J/s)
Pressure
Pascal
Pa (N/m²)
Electric charge
Coulomb
C (s-A)

Linear motion (also called rectilinear motion) is motion along a straight line, and can therefore be described mathematically using only one spatial dimension. The linear motion can be of two types: uniform linear motion with constant velocity or zero acceleration; non uniform linear motion with variable velocity or non-zero acceleration. The motion of a particle (a point-like object) along a line can be described by its position , which varies with (time). An example of linear motion is an athlete running 100m along a straight track.
Linear motion is the most basic of all motion. According to Newton's first law of motion, objects that do not experience any net force will continue to move in a straight line with a constant velocity until they are subjected to a net force. Under everyday circumstances, external forces such as gravity and friction can cause an object to change the direction of its motion, so that its motion cannot be described as linear
Uniform linear motion’s formula: v = s/t
V = velocity (m/s), s = distance (m), t = time (second)
Non uniform linear motion’s formula: vt = vo + a . t
Vt = finished velocity (m/s), vo = started velocity (m/s), a = acceleration (m/s²), t = time


The first newton’s law
“If the resultant force on an object is equal to zero, the object initially silent will continue to be silent, while the original object moving will continue to move at a steady place”.
Formula: ∑f = 0               ∑f= f1 + f2
F = Energy (Newton)
The second newton’s law
“Acceleration produced by a net force on an object, it is proportional to the net force and inversely proportional to the mass of the object”.
Formula:  F = m . a             a = f/m
F = energy (newton), m = mass (kg), a = acceleration (m/s²)
The third newton’s law
“If the first object takes action on both object, the object reaction force arising from the second object to the first object in the same magnitude but different direction”
Formula:  fa = -fb
Fa = action (newton), fb = reaction (newton)
Work
Work is the product of force component in the direction of displacement in large displacement. Work only carried by forces which work on object. An object will be said “doing something” on the object if the force caused it to move.
Formula: w= f.s
W= work (joule), F= force (newton), S= displacement (meter)
Energy
Energy is a capability to carry out an effort.
Kinetic energy is a capability to carry out an effort. Formula: Ek= ½ . m. v²
Ek= Kinetic energy (joule), M= mass (kg), V= (speed)
Potential energy is energy of an object caused of its position (stand or height).
Formula: Ep= m. g. h
Ep= potential energy (joule), M= mass (kg), g= gravity (m/s²), h= the position of the object
Vibration
Vibration is periodical vice-verse movement passes trough the balance point. One vibration is one vice-verse movement.
Formula: F= -k.y
F= style (newton), k= styled deasion (N/m), y= deviation (m)
Wave
A wave is a propagate direction.  Wave carries energy during propagation.
Transverse wave is a moving wave that has perpendicular direction to the direction of energy transfer. Example: waves on the water surface
Longitudinal wave is a wave in which displacement of the medium in the same direction as, or the opposite direction of travel of waves. Example: sound waves
Pressure
Pressure is a physic unit for the real force and divided by wade. Formula:  .
P= pressure (N/m²), f= model (N), A= wade foundation (m²)
Momentum
Momentum is defined as the multiplication of the mass and speed. Formula: P= m.v
P= momentum (kg, m/s), M= mass (kg), V= speed (m/s).
Heat
Heat is the energy that moved by the differences of temperature. Formula: Q= M. C. Δt
Q= heat received a substance (joule), m= mass substance (kg), c= heat in the type of substance (joule/kg), Δt= changes in temperature (⁰C)
Temperature
Temperature is the degree of hotness and coldness of an object. Temperature is measured by thermometer. Kinds of thermometer are; Celsius thermometer, Reamer thermometer, Fahrenheit thermometer, and Kelvin thermometer.
Formula =
Xa and Ya = top fixed point of thermometer
Xb and Yb = the temperature on thermometer
Xc and Yc = down fixed point of thermometer

informasi untuk mahasiswa pendidikan fisika dan pendidikan BI

nilai akhir semester kalian nanti akan di print out (tidak saya publish di blog), tunggu saja informasi selanjutnya..