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Jul 3, Learn about the elementary laws of physics, as well as Newton and Einstein's Together, these three principles that Newton outlined form the basis of classical Newton's 3 Laws of Motion Explain How Movement Works.
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Light behaves similarly in that it bounces off walls and bends around corners, and that the crests and troughs of the wave can add up or cancel out. Added wave crests result in brighter light, while waves that cancel out produce darkness. The color emitted corresponds to the distance between the crests, which is determined by the speed of the ball's rhythm.

Waves of matter : Matter can also behave as a wave. This ran counter to the roughly 30 years of experiments showing that matter such as electrons exists as particles. In , German physicist Max Planck sought to explain the distribution of colors emitted over the spectrum in the glow of red-hot and white-hot objects, such as light-bulb filaments. Somehow, colors were quantized!

This was unexpected because light was understood to act as a wave, meaning that values of color should be a continuous spectrum. This seemed so strange that Planck regarded quantization as nothing more than a mathematical trick. According to Helge Kragh in his article in Physics World magazine, " Max Planck, the Reluctant Revolutionary ," "If a revolution occurred in physics in December , nobody seemed to notice it. Planck was no exception …". Planck's equation also contained a number that would later become very important to future development of QM; today, it's known as "Planck's Constant.

Quantization helped to explain other mysteries of physics. In , Einstein used Planck's hypothesis of quantization to explain why the temperature of a solid changed by different amounts if you put the same amount of heat into the material but changed the starting temperature.

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In , Johannes Rydberg derived an equation that described the spectral lines emitted by hydrogen, though nobody could explain why the equation worked. They could "jump" between special orbits, and the energy produced by the jump caused specific colors of light, observed as spectral lines. Though quantized properties were invented as but a mere mathematical trick, they explained so much that they became the founding principle of QM.

In , Einstein published a paper, " Concerning an Heuristic Point of View Toward the Emission and Transformation of Light ," in which he envisioned light traveling not as a wave, but as some manner of "energy quanta. This would also apply, as would be shown a few years later, when an electron "jumps" between quantized orbits. With this new way to envision light, Einstein offered insights into the behavior of nine different phenomena, including the specific colors that Planck described being emitted from a light-bulb filament.

It also explained how certain colors of light could eject electrons off metal surfaces, a phenomenon known as the "photoelectric effect. Third law of thermodynamics :. Maxwell's equations give the time-evolution of the electric and magnetic fields due to electric charge and current distributions. Given the fields, the Lorentz force law is the equation of motion for charges in the fields.

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Gauss's law for magnetism. Faraday's law. These equations can be modified to include magnetic monopoles , and are consistent with our observations of monopoles either existing or not existing; if they do not exist, the generalized equations reduce to the ones above, if they do, the equations become fully symmetric in electric and magnetic charges and currents.

Indeed, there is a duality transformation where electric and magnetic charges can be "rotated into one another", and still satisfy Maxwell's equations. These laws were found before the formulation of Maxwell's equations. They are not fundamental, since they can be derived from Maxwell's Equations.

Mysterious Quantum Rule Reconstructed From Scratch

Nonetheless they are still very effective for simple calculations. Classically, optics is based on a variational principle : light travels from one point in space to another in the shortest time. In geometric optics laws are based on approximations in Euclidean geometry such as the paraxial approximation. In physical optics , laws are based on physical properties of materials. In actuality, optical properties of matter are significantly more complex and require quantum mechanics.

Quantum mechanics has its roots in postulates. This leads to results which are not usually called "laws", but hold the same status, in that all of quantum mechanics follows from them. Solving this wave equation predicts the time-evolution of the system's behaviour, analogous to solving Newton's laws in classical mechanics.

Other postulates change the idea of physical observables; using quantum operators ; some measurements can't be made at the same instant of time Uncertainty principles , particles are fundamentally indistinguishable. Another postulate; the wavefunction collapse postulate, counters the usual idea of a measurement in science.

Planck—Einstein law : the energy of photons is proportional to the frequency of the light the constant is Planck's constant , h. Heisenberg uncertainty principle : Uncertainty in position multiplied by uncertainty in momentum is at least half of the reduced Planck constant , similarly for time and energy ;.

There is no way to keep track of particles physically, labels are only used mathematically to prevent confusion. Applying electromagnetism, thermodynamics, and quantum mechanics, to atoms and molecules, some laws of electromagnetic radiation and light are as follows. Chemical laws are those laws of nature relevant to chemistry. Historically, observations led to many empirical laws, though now it is known that chemistry has its foundations in quantum mechanics.

The most fundamental concept in chemistry is the law of conservation of mass , which states that there is no detectable change in the quantity of matter during an ordinary chemical reaction. Modern physics shows that it is actually energy that is conserved, and that energy and mass are related ; a concept which becomes important in nuclear chemistry. Conservation of energy leads to the important concepts of equilibrium , thermodynamics , and kinetics. Additional laws of chemistry elaborate on the law of conservation of mass.

Joseph Proust 's law of definite composition says that pure chemicals are composed of elements in a definite formulation; we now know that the structural arrangement of these elements is also important.

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Dalton 's law of multiple proportions says that these chemicals will present themselves in proportions that are small whole numbers; although in many systems notably biomacromolecules and minerals the ratios tend to require large numbers, and are frequently represented as a fraction. Some mathematical theorems and axioms are referred to as laws because they provide logical foundation to empirical laws. Examples of other observed phenomena sometimes described as laws include the Titius—Bode law of planetary positions, Zipf's law of linguistics, and Moore's law of technological growth.

Many of these laws fall within the scope of uncomfortable science. Other laws are pragmatic and observational, such as the law of unintended consequences. By analogy, principles in other fields of study are sometimes loosely referred to as "laws".


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These include Occam's razor as a principle of philosophy and the Pareto principle of economics. The observation that there are underlying regularities in nature dates from prehistoric times, since the recognition of cause-and-effect relationships is an implicit recognition that there are laws of nature. The recognition of such regularities as independent scientific laws per se , though, was limited by their entanglement in animism , and by the attribution of many effects that do not have readily obvious causes—such as meteorological , astronomical and biological phenomena—to the actions of various gods , spirits , supernatural beings , etc.

Observation and speculation about nature were intimately bound up with metaphysics and morality. According to a positivist view, when compared to pre-modern accounts of causality , laws of nature replace the need for divine causality on the one hand, and accounts such as Plato 's theory of forms on the other.

In Europe, systematic theorizing about nature physis began with the early Greek philosophers and scientists and continued into the Hellenistic and Roman imperial periods, during which times the intellectual influence of Roman law increasingly became paramount.

The formula "law of nature" first appears as "a live metaphor" favored by Latin poets Lucretius , Virgil , Ovid , Manilius , in time gaining a firm theoretical presence in the prose treatises of Seneca and Pliny. Why this Roman origin?

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According to [historian and classicist Daryn] Lehoux's persuasive narrative, [16] the idea was made possible by the pivotal role of codified law and forensic argument in Roman life and culture. For the Romans. When we read Seneca's Natural Questions , and watch again and again just how he applies standards of evidence, witness evaluation, argument and proof, we can recognize that we are reading one of the great Roman rhetoricians of the age, thoroughly immersed in forensic method. And not Seneca alone.

Legal models of scientific judgment turn up all over the place, and for example prove equally integral to Ptolemy 's approach to verification, where the mind is assigned the role of magistrate, the senses that of disclosure of evidence, and dialectical reason that of the law itself. The precise formulation of what are now recognized as modern and valid statements of the laws of nature dates from the 17th century in Europe, with the beginning of accurate experimentation and development of advanced forms of mathematics. During this period, natural philosophers such as Isaac Newton were influenced by a religious view which held that God had instituted absolute, universal and immutable physical laws.

The rules according to which these changes take place I call the 'laws of nature'. Natural law in the political sense, conceived as universal i. The distinction between natural law in the political-legal sense and law of nature or physical law in the scientific sense is a modern one, both concepts being equally derived from physis , the Greek word translated into Latin as natura for nature.