Can Planck's constant be measured with classical mechanics?

1997 ◽  
Vol 11 (3) ◽  
pp. 223-243 ◽  
Author(s):  
Hasok Chang
Keyword(s):  
Classical Mechanics ◽  
Planck’S Constant ◽  
Planck's Constant

scholarly journals Position Dependent Planck’s Constant in a Frequency-Conserving Schrödinger Equation

Symmetry ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 490
Author(s):  
Rand Dannenberg
Keyword(s):  
Schrödinger Equation ◽  
Schrodinger Equation ◽  
Reference Frames ◽  
Classical Mechanics ◽  
Planck’S Constant ◽  
The Earth ◽  
Planck's Constant ◽  
Lagrangian Densities ◽  
The Impact ◽  
Potential Frequency

There is controversial evidence that Planck’s constant shows unexpected variations with altitude above the earth due to Kentosh and Mohageg, and yearly systematic changes with the orbit of the earth about the sun due to Hutchin. Many others have postulated that the fundamental constants of nature are not constant, either in locally flat reference frames, or on larger scales. This work is a mathematical study examining the impact of a position dependent Planck’s constant in the Schrödinger equation. With no modifications to the equation, the Hamiltonian becomes a non-Hermitian radial frequency operator. The frequency operator does not conserve normalization, time evolution is no longer unitary, and frequency eigenvalues can be complex. The wavefunction must continually be normalized at each time in order that operators commuting with the frequency operator produce constants of the motion. To eliminate these problems, the frequency operator is replaced with a symmetrizing anti-commutator so that it is once again Hermitian. It is found that particles statistically avoid regions of higher Planck’s constant in the absence of an external potential. Frequency is conserved, and the total frequency equals “kinetic frequency” plus “potential frequency”. No straightforward connection to classical mechanics is found, that is, the Ehrenfest’s theorems are more complicated, and the usual quantities related by them can be complex or imaginary. Energy is conserved only locally with small gradients in Planck’s constant. Two Lagrangian densities are investigated to determine whether they result in a classical field equation of motion resembling the frequency-conserving Schrödinger equation. The first Largrangian is the “energy squared” form, the second is a “frequency squared” form. Neither reproduces the target equation, and it is concluded that the frequency-conserving Schrödinger equation may defy deduction from field theory.

scholarly journals Development and Students’ Perception on Teaching Aids of Photoelectric Effect Experiment Using Leds

2019 ◽  
Vol 7 (3) ◽  
pp. 253-261
Author(s):  
Hartono Bancong ◽  
Ana Dhiqfaini Sultan ◽  
Subaer Subaer ◽  
Muris Muris
Keyword(s):  
Cost Effective ◽  
Photoelectric Effect ◽  
High Price ◽  
Planck’S Constant ◽  
Teaching Aids ◽  
Modern Physics ◽  
User Friendly ◽  
Planck's Constant ◽  
D Model ◽  
Effect Experiment

The photoelectric effect experiment generally uses a very sophisticated and expensive apparatus. Some high schools and even universities in Indonesia cannot afford to conduct this experiment because of the high price of the apparatus. The purpose of this study was to develop a user-friendly, and cost-effective teaching aids which can be used to demonstrate the concepts of modern physics related to the photoelectric effect. The stages of this study employed the Four-D model, namely define, design, develop, and disseminate. Based on experts and practitioner evaluation, the developed teaching aids and practicum devices of photoelectric effect experiment were found to be valid and reliable. The results of the experiment by using this developed teaching aids of the photoelectric effect showed that there is a linear relationship between the stopping potential and the frequency of light emitted by the LED. These results are consistent with Millikan's experimental results, the first physicist who succeed in proving Einstein's hypothesis of the photoelectric effect, that in the photoelectric effect the stopping potential does not depend on the intensity of light but depends only on the frequency of light. In this study, the Planck’s constant value obtained is 6.408x10-34 J.s. Although this value is slightly smaller than the accepted value of Planck's constant that is 6.626x10-34 J.s, it is good enough considering the instrumental error occurred during the measurement of current and voltage. Furthermore, the students’ perception of the developed teaching aids and practicum devices of the photoelectric effects experiment are 74.9% (good) and 80.2% (very good), respectively. This indicates that the photoelectric effect experiment teaching aids and practicum devices that have been developed can be used to demonstrate and prove the concepts of modern physics related to the photoelectric phenomena correctly.Keywords: Teaching Aids, Photoelectric Effect, Students’ Perception

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