14
1.
THE CHARGE OF THE ELECTRON
,
_
.
-
EXPERIMENT 1—1
‘
.
’
TO MEASURE THE CHARGE OF THE .ELECTRON
Âppamz‘us.—The cohdenser
of gure 1—3 consists of two thick
'
metal plates PP which have been carefully faced and are separated
by insulator strips' B of
adenite and uniform thickness.
The
*
plates may be two or more inches square and three to ve mllll—
meters apart. _The condenser is rigidly mounted in a horizontal
position. Several small holes in the top plate, under the cover C,
-
P
_
K-_
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M
P
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P
Il
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B
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SIDE VIEW
_‘I‘OP VIEW
‘
FIG. 1—3.
Measurement of the charge on oil drops.
'
_
allow drops of oil, spraÿed from an atomizer, to fall into the region
«
between the plates. The process
of atomizing the oil serves to
eleCtrically charge the drops. Glass windows across the front and
'
back sides allow observation of the drops and eliminate air cur; _ _—
rents.
Light from a ash lamp, L, is reected from a drop and is
in a long focus microscope T, as
in the gure.
In the
of, the microscope there is a nely divided
The
magniclation is such that each small division corresponds to
…
cm.
"
«A dark background-is provided in the corner
Â,e1therby.meansof a cardboard screen K, Which has a vertical
sht, or
L shaped insulators"between-"the
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