Page:Messungen an Becquerelstrahlen.djvu/4

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By means of this arrangement, rays of a certain velocity find quite automatically the angle, at which the compensation occurs at a given field strength, and which allows them to leave the condenser. Thus electrons of all velocities and corresponding masses will hit upon the film, and thus produce a curve which allows to determine the mass as a function of velocity. Consequently, a single exposition suffices to test the various theories of the electron. The equations of motion of the electrons assume the following form:

I

Here, mean the specific charge and mass of the electron. The direction of increasing is the direction of the magnetic field . While the - and -axes coincide with the plane of the condenser plates, is perpendicular to this plane. Within the condenser, the direction of motion forms the angle with . Due to the spiral motion in the pure magnetic field, however, the direction deviates from the initial one, so that the impact point upon the film, lies in the direction which somewhat deviates from . If one integrates the preceding equations and if one sets , then it follows:

II

If one furthermore sets , and

then one obtains by repeated integration:

III

If one denotes the values of and (present at the impact point of the electron) by index , and if one furthermore sets , then one finds:

IV

By insertion of (3) into (1) and (2) it follows:

(1a)
(2a)

is given from these equations, and from that the velocity of the ray hitting at .

Since slightly differs from , one proceeds just so, as if the electron (which is hitting at ) would have moved with the previously calculated velocity at a circular path in a vertical plane, which passes through the radium granule and .

Now, the force acting in the magnetic field is:

(4)

However, as it is shown by a simple calculation, it is:

(5)

Now if one considers, that according to Lorentz:

(6)

then the relations (4), (5) and (6) give

(7)

While according to Maxwell under employment of Abraham's formula, and when we set :

(8)

Obviously only that theory is valid, for which is a real constant for any value of within the observational errors.


The experiments.

I omit at this place the experiments, which I have undertaken to test my relativity principle. The report shall suffice,