DOC.
23
171
This relation
can
be checked
experimentally
since the
velocity
of the
electron
can
also
be measured
directly,
e.g., using
rapidly
oscillating
electric
and
magnetic
fields.
2.
It follows
from
the derivation for the kinetic
energy
of the
electron that the
potential
difference traversed
by
the electron
and
the
velocity
v
attained
by
it
must
be
related
by
the
equation
P
=
Xdx
=
f
V2
1
1

V
V
7

1
3.
We
calculate the
radius of
curvature
R
of the
path when
a magnetic
force
N,
which acts perpendicular to
the
velocity of
the electron, is
present
(as
the
only
deflecting force).
From
the
second
of
equations
(A) we
obtain

I
»
K
Tfi

R
 p
1 "
or
R
=
yi
ä.
e
v
V
1

1
v
V
v
V
7
1
These
three relations
are a
complete
expression
of the
laws
by
which
the
[46]
electron
must
move
according
to
the
theory presented
here.
In conclusion, let
me
note
that
my
friend
and
colleague
M.
Besso
steadfastly stood
by me
in
my
work
on
the
problem
here discussed,
and
that
I
am
indebted
to him
for
many a
valuable
suggestion.
[47]
Bern, June 1905.
(Received
on
30
June
1905)