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What Is Constant In Physics

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What Is Oscillation Very Short Answer

01 – Motion with Constant Acceleration in Physics (Constant Acceleration Equations)

Oscillation is the process of moving back and forth regularly, like the oscillation of a fan that cools off the whole room, or the oscillation of a movie plot that makes you laugh and cry. Oscillation is from the Latin word oscillare for to swing, so oscillation is when something is swinging back and forth.

What Is Plancks Quantum Hypothesis

The quantum hypothesis, first suggested by Max Planck in 1900, postulates that light energy can only be emitted and absorbed in discrete bundles called quanta. Energy, E, is described by the equation: E = nhf, where n is an integer and h is Plancks constant, equal to 6.626068 × 1034 Joule-second .

Are The Constants Of Physics Constant

So far, they seem to bebut nobody really understands why

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When Max Born addressed the South Indian Science Association in November 1935, it was a time of great uncertainty in his life. The Nazi Party had already suspended the renowned quantum mechanics physicist’s position at the University of Gottingen in 1933. He had been invited to teach at Cambridge, but it was temporary. Then, the Party terminated his tenure at Gottingen in the summer of 1935. Born took up an offer to work with C. V. Raman and his students for six months at the Indian Institute of Science in Bangalore. While there, he found that his family had lost its German citizenship rights. He was stateless and without a permanent home. And then, there was this uncertainty about two numbers.

The scientific world had been coming to terms with two numbers that had emerged after a series of discoveries and theories in the previous four decades. They were unchanging and they had no units. One, the fine structure constant, defined the strength of interactions between fundamental particles and light. It is expressed as 1/137. The other, mu, related the mass of a proton to an electron.

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Is The Universe Constantly Changing

The composition of the universe the elements that are the building blocks for matter is ever-changing and evolving, thanks to the lives and deaths of stars, according to a study. The study, published in the journal Science, describes how these elements form as stars grow and explode, and fade and merge.

What Keeps The Universe Changing

Fundamental physical constants * .

Universe Dark Energy-1 Expanding Universe Astronomers theorize that the faster expansion rate is due to a mysterious, dark force that is pulling galaxies apart. One explanation for dark energy is that it is a property of space. Albert Einstein was the first person to realize that empty space is not nothing.

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How Is The Stefan Boltzmann Constant Used In Si Units

Furthermore, the StefanBoltzmann constant allows for temperature to be converted to units for intensity , which is power per unit area. Since the 2019 redefinition of the SI base units, the StefanBoltzmann constant is given exactly rather than measured in experiment. The value is given in SI units by

Measurements Of Boltzmann Constant K:

In order to link the fixed numerical value of Boltzmanns constant to the previous definitions of the Kelvin, and in particular to determine the precision and errors, it is necessary to measure the value of Boltzmanns current in terms of SI units as accurately as possible, and also to understand and estimate all errors in the measurement. Several measurements of Boltzmanns constants are being performed in laboratories around the world, particularly at several European and US laboratories.

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Boltzmann Constant K And The New Framework For The Si System Of Units:

With the 26th General Conference on Weights and Measures on 16 November 2018 the SI system of units switched from the previous method where units are fixed and numerical values of fundamental constants are variable, i.e. determined experimentally, to the new method where the numerical values of the set of fundamental constants is fixed, and the units are defined such, that their definition results in the fixed numerical values of the set of fundamental constants. This switch to a new definition of the SI system requires international agreements, and decisions by international organizations, and this process was completed on 16 November 2018.

Electromagnetic Interaction Is Weak

RC Circuit – Definition of the Time Constant – AP Physics C

The relatively low value of it is approximately equal to 1/137 implies that the electromagnetic interaction is weak. The main consequence of this is that electrons orbit some distance from their atoms, so they are free to form chemical bonds and build up molecules. This property made it possible for matter and energy to form stars and planets. Indeed, some physicists have argued that we owe our very existence to the exact value of , because if it were slightly bigger or smaller, stars might not been have able to synthesize heavier elements like carbon, and life as we know it wouldnt exist.

Precise measurements of make it possible to rigorously test relationships between elementary particles. These relationships are described by the equations that make up the Standard Model of particle physics, and any discrepancy between the models predictions and experimental observations may provide evidence of new physics.

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What Do You Mean By Oscillatory Motion

A motion repeating itself is referred to as periodic or oscillatory motion. An object in such motion oscillates about an equilibrium position due to a restoring force or torque. This motion is important to study many phenomena including electromagnetic waves, alternating current circuits, and molecules.

What Is Force Constant In Physics

4/5Force constantspring constant in physicsphysicsforcespringfull detail here

The unit of the force constant is Newton/meter . According to Robert Hook, the force that a spring applies when it is stretched or compressed is

One may also ask, how do you find the force constant? F is the restoring force of the spring directed towards the equilibrium. k is the spring constant in N.m. x is the displacement of the spring from its equilibrium position.Spring Constant Formula.


Considering this, what is spring constant physics?

springconstant. Noun. A characteristic of a spring which is defined as the ratio of the force affecting the spring to the displacement caused by it.

What is Hooke’s Law constant?

Hooke’s Law states that the force needed to compress or extend a spring is directly proportional to the distance you stretch it. As an equation, Hooke’s Law can be represented as F = kx, where F is the force we apply, k is the spring constant, and x is the extension of the material .

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Who Calculated Plancks Constant

Robert Millikan made the first measurement of Plancks constant in 1916. The best current value for Plancks constant is 6.62607554 x 10-34 J · s. In this experiment, you will use light emitting diodes to measure Plancks constant. You should be familiar with semiconductors and diodes from Modern Physics.

Numerological Explanations And Multiverse Theory


As a dimensionless constant which does not seem to be directly related to any mathematical constant, the fine-structure constant has long fascinated physicists.

Arthur Eddington argued that the value could be “obtained by pure deduction” and he related it to the Eddington number, his estimate of the number of protons in the universe. This led him in 1929 to conjecture that the reciprocal of the fine-structure constant was not approximately but precisely the integer137. By the 1940s experimental values for 1/ deviated sufficiently from 137 to refute Eddington’s arguments.

The fine-structure constant so intrigued physicist Wolfgang Pauli that he collaborated with psychoanalyst Carl Jung in a quest to understand its significance. Similarly, Max Born believed that if the value of differed, the universe would degenerate, and thus that = 1/137 is a law of nature.

Richard Feynman, one of the originators and early developers of the theory of quantum electrodynamics , referred to the fine-structure constant in these terms:

Conversely, statistician I. J. Good argued that a numerological explanation would only be acceptable if it could be based on a good theory that is not yet known but “exists” in the sense of a Platonic Ideal.

Attempts to find a mathematical basis for this dimensionless constant have continued up to the present time. However, no numerological explanation has ever been accepted by the physics community.

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Boltzmann Constant K Links Temperature With Energy

In an ideal gas in equilibrium at temperature T, the average kinetic energy per molecule is:

1/2 m< v^2> = 3/2 kT, where k is Boltzmanns constant.

More generally in a classical system of particles, observing Boltzmann statistics, oscillators etc. the average energy in equilibrium per degree of freedom is 1/2 kT.

Note that there are other systems observing Bose-Einstein, or Fermi-Dirac statistics where other relationships apply.

Spatial Variation Australian Dipole

In September 2010, researchers from Australia said they had identified a dipole-like structure in the variation of the fine-structure constant across the observable universe. They used data on quasars obtained by the Very Large Telescope, combined with the previous data obtained by Webb at the Keck telescopes. The fine-structure constant appears to have been larger by one part in 100,000 in the direction of the southern hemisphere constellation Ara, 10 billion years ago. Similarly, the constant appeared to have been smaller by a similar fraction in the northern direction, 10 billion years ago.

In October 2011, Webb et al. reported a variation in dependent on both redshift and spatial direction. They report “the combined data set fits a spatial dipole” with an increase in with redshift in one direction and a decrease in the other. “Independent VLT and Keck samples give consistent dipole directions and amplitudes….”

In 2020, the team verified their previous results, finding a dipole structure in the strength of the electromagnetic force using the most distant quasar measurements. Observations of the quasar of the universe at only 0.8 billion years old with AI analysis method employed on the Very Large Telescope found a spatial variation preferred over a no-variation model at the 3.9

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Determining The Recoil Velocity Of Atoms

Measurements of generally begin by determining how strongly atoms recoil when they absorb photons. The kinetic energy of this recoil reveals how massive the atoms are. Next, the electrons mass is calculated using the precisely known ratio of the atoms mass to that of an electron. Finally, is calculated from the electrons mass and the binding energy of a hydrogen atom, the value of which is likewise well known from spectroscopy measurements.

In the new work, researchers led by Saïda Guellati-Khélifa at the Kastler Brossel Laboratory in Paris cooled atoms of rubidium to a few degrees above absolute zero in a vacuum chamber. They then created a quantum superposition of two states of the atoms using laser pulses. The first state corresponds to atoms that recoil when they absorb photons and the second state to atoms that do not recoil.

The two possible versions of each of type of atom propagate through the experimental chamber along different paths. The researchers then applied a second set of laser pulses to re-join the two halves of the superposition.

What Is Constant Acceleration In Physics

Values of Physical Constants: Physics/Chemistry (ISC, CBSE, ICSE, NEET,JEE Main)

4.3/5Constant Accelerationconstant accelerationconstantconstant accelerationconstantconstantaccelerating

Definition of Constant AccelerationAcceleration is defined as the rate that your speed changes, or how fast your speed is changing. An object that travels with constant acceleration has a speed that changes by the same amount each second.

Subsequently, question is, what is the definition of average acceleration? Average acceleration is the change in velocity divided by an elapsed time. For instance, if the velocity of a marble increases from 0 to 60 cm/s in 3 seconds, its average acceleration would be 20 cm/s/s. This means that the marble’s velocity will increase by 20 cm/s every second.

Consequently, what is the constant acceleration equation?

Acceleration=Change in velocityChange in time. More precisely, the constant acceleration a is given by the formula. a=vvt2t1, where v is the velocity at time ti. Since velocity is a vector, so is acceleration.

When velocity is constant What is acceleration?

If your acceleration is constant as time flow it’s velocity increase w.r.t. time. An object is moving with a velocity v=5+2t.t m/s for its seconds.

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Fundamental Constant Values In Physics

Speed of light in vacuum = c

Plancks constant = h

In physics, we deal with various dimensions. In order to set the dimensions of an entity, the time length of an event, or the density of the fluid we need to compare them with the other entities. It can be used as a reference. These entities are the constants of physics. There are many physical constants in science, some of the most widely recognized being the speed of light in vacuum c, the gravitational constant G, the Planck constant h, the electric constant 0, and the elementary charge e etc.

For example, 6.02214 x 10²³ mol-1 is the value of Avogadro’s number, it remains the same everywhere.

There are various fundamental physics constants that help us to describe the universe as completely as possible a few are listed below in the table:


1.3047 K * A/

In meter: 2.42 x 10-¹²m

In Angstrom = 0.242 Å

a0 = 40 h²/e²me

0.0529 m

= ²k4/60h³c²

5.67 x 10-8Js-¹m-²K-4

6.6524587321 x 10-29 m²

Rest mass of the electron

me = 2Rh/c2

There are so many constants besides those we mentioned above in the table, but some physics constants are recognized widely.

Constant values in physics that are most popular among all the physical constants are listed below in the table:


Speed of light in the vacuum

6.673 x 10-¹¹ Nm²/kg²

e, qe

1.602176634 x 10-19 C

8.9875517923 x 109 kg.m³. s-4.A-2

8.3144598 x 10³ amu.m²/s²K

8.3144598 x 10-2 mol

8.3144598 m³ .Pa/K.mol

Fundamental Constants And The Si System Of Units:

Each fundamental constant Q is a product of a number and a base unit :

Q = x ,

for example Boltzmanns constant is:k = 1.380 649 x 10-23 JK-1.

Thus we have two ways to define the SI system of SI base units:

  • we can fix the units , and then measure the numerical values of fundamental constants in terms of these units
  • we can fix the numbers of fundamental constants, and then define the units thus that the fundamental constants have the numerical values
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    Value Of The Constant

    The Coulomb constant is the constant of proportionality in Coulomb’s law,

    F =k_}}}\mathbf } _}

    where êr is a unit vector in the r-direction. In SI:

    k }=}},}

    where is the vacuum permittivity. This formula can be derived from Gauss’ law,

    S 0 \cdot }\mathbf =}}}

    Taking this integral for a sphere, radius r, centered on a point charge, the electric field points radially outwards and is normal to a differential surface element on the sphere with constant magnitude for all points on the sphere.

    S r 2 \cdot }\mathbf =|\mathbf |\int _dA=|\mathbf |\times 4\pi r^}

    Noting that E = F/q for some test charge q,

    F 0 \mathbf & =}}}}\mathbf } _=k_}}}\mathbf } _\\\therefore k_}& =}}\end}}

    Coulomb’s law is an Inverse Square Law, and thereby similar to many other scientific laws ranging from gravitational pull to light attenuation. This law states that a specified physical quantity is inversely proportional to the square of the distance.



    Spring Constant Dimensional Formula

    Physics Constants for GCE A Level

    According to Hookes law, we know that,

    F= -kx


    k= -F/x

    Now we know that the unit of force is given as Newton , or as kg m/s2.

    Therefore, we can write the dimensional unit as .

    We also know the dimensional unit of x is given as

    Applying spring constant formula, we get,

    k = – \}\]

    k= –

    The spring constant unit is in terms of Newton per meter .

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    Nature Of Physical Constants

    Based on nature, the fundamental constants are grouped into three categories namely-

    • A: Characteristic of a particular system.
    • B: Characteristic of a class of physical phenomena.
    • C: Universal Constants.

    Few Physical constants can take the dimensional form like speed of light in contrast, few are dimensionless like- fine structure constant. Some physical constants are material constants which means they possess constant value for a material.

    A constant can be expressed using multiple equivalent units like SI, natural units, atomic mass unit, CGS units etc. Some physical constant redefined by fixing the SI values. But this certainly increases the uncertainty in the value of physical constants.

    What Is Planck’s Constant And Why Does The Universe Depend On It

    If you’re a fan of the Netflix series “Stranger Things,” you’ve seen the climatic season three scene, in which Dustin tries to cajole his brainy long-distance girlfriend Suzie over a ham radio connection into telling him the precise value of something called Planck’s constant, which also happens to be the code to open a safe that contains the keys needed to close the gate to a malevolent alternative universe.

    But before Suzie will recite the magic number, she exacts a high price: Dustin has to sing the theme song to the movie “The NeverEnding Story.”

    This may all have led you to wonder: What exactly is Planck’s constant, anyway?

    The constant devised in 1900 by a German physicist named Max Planck, who would win the 1918 Nobel Prize for his work is a crucial part of quantum mechanics, the branch of physics which deals with the tiny particles that make up matter and the forces involved in their interactions. From computer chips and solar panels to lasers, “it’s the physics that explains how everything works.”

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