摘要:

A cheap electron accelerator is constructed, and possible experiments that could be investigated are suggested. The limitations of the system are also discussed.

ISSN:0002-9505    

DOI:10.1119/1.1987000

出版商:American Association of Physics Teachers    

年代:1972

数据来源: AIP

摘要:

It is shown that Lagrange's equations may be obtained by projecting Newton's second law onto the moving tangent vectors associated with a change in the generalized coordinates qi. This exposes the Lagrange equation for qi as the component of the force equation in the indicated direction.

ISSN:0002-9505    

DOI:10.1119/1.1987001

出版商:American Association of Physics Teachers    

年代:1972

数据来源: AIP

摘要:

A method to determine the Lagrangian with the use of complex numbers is described. The kinetic energy is found from the magnitude of the complex velocity, and the potential energy is found from the real part of the complex displacement. Finally this method may be used to determine generalized forces with Lagrange's method of undetermined multipliers.

ISSN:0002-9505    

DOI:10.1119/1.1987002

出版商:American Association of Physics Teachers    

年代:1972

数据来源: AIP

摘要:

A method is outlined for obtaining the exact Green's function solutions for the two-spin-1/2Heisenberg ferromagnet utilizing commutator and anticommutator Green's functions. It is observed that the exact solutions can be obtained much more easily and readily when utilizing anticommutator Green's functions than when utilizing commutator Green's functions.

ISSN:0002-9505    

DOI:10.1119/1.1987003

出版商:American Association of Physics Teachers    

年代:1972

数据来源: AIP

摘要:

A matrix method for finding the energy eigenvalues of one-dimensional systems is given. The method utilizes the correspondence principle to find the separation of every two successive eigenvalues and the uncertainty principle to find the lowest energy. The harmonic oscillator and the infinite square well are solved exactly, and the WKB approximation for bound state energies is deduced.

ISSN:0002-9505    

DOI:10.1119/1.1987004

出版商:American Association of Physics Teachers    

年代:1972

数据来源: AIP

摘要:

A discussion of a laboratory experiment involving a parallel LC circuit containing a real inductor(RL ≢ 0)is presented. By choosing component values to be confined to certain ranges, equations are presented for the (1) ratio of the output to input voltages, (2) Q of the circuit, and (3) phase of the output signal relative to the input. It is found that the phase goes to zero as the frequency decreases when a real inductor is used, rather than toπ/2as is the case for an ideal inductor(RL = 0).Experimental results are presented.

ISSN:0002-9505    

DOI:10.1119/1.1987005

出版商:American Association of Physics Teachers    

年代:1972

数据来源: AIP

摘要:

A series of computer-generated films is described, intended to serve as pedagogic aids in presenting ideas concerning the motion of electrons in periodic potentials. Three films have been produced which illustrate the following phenomena: (A) propagation of wave packets of several different mean energies through the ideal crystal lattice; (B) reflection and transmission of a wave packet incident on a crystal from free space, for mean energy values lying (1) in an allowed energy band of the crystal and (2) in a forbidden gap of the crystal; and (C) scattering of a wave packet by an impurity atom in the lattice.

ISSN:0002-9505    

DOI:10.1119/1.1987006

出版商:American Association of Physics Teachers    

年代:1972

数据来源: AIP

摘要:

A simple derivation of the usual expression for the Thomas precession angle whenv≪cis connected in a simple manner with the time difference in the clock paradox.

ISSN:0002-9505    

DOI:10.1119/1.1987007

出版商:American Association of Physics Teachers    

年代:1972

数据来源: AIP

摘要:

The objective of this experiment is to familiarize the student with the impulse theorem, electron dynamics, and magnetic field contours. He is challenged to obtain accurate as well as precise measurements with suboptimum apparatus through correct analysis. He also investigates the influence of various systematic errors using model calculations on a small computer.

ISSN:0002-9505    

DOI:10.1119/1.1987008

出版商:American Association of Physics Teachers    

年代:1972

数据来源: AIP

摘要:

The eigensolutions of the Schrödinger equation for the motion of a charged particle in a uniform magnetic field depend on the choice of electromagnetic gauge. In the Landau gauge it is hard to discern a relationship between the eigensolutions and the circular or helical orbits of classical theory. In this paper a wave packet is constructed from the Landau gauge eigensolutions which simulates the classical motion in the plane perpendicular to the magnetic field. Some properties of the wave packet are discussed.

ISSN:0002-9505    

DOI:10.1119/1.1987009

出版商:American Association of Physics Teachers    

年代:1972

数据来源: AIP