16
1.
THE CHARGE OF THE ELECTRON
scale divisions to be clearly distinguished. Adjust the focus of the
microscope as a whole and also that of its eyepiece until there is
no parallax between the streak of light and the scale. Do not
change the focus during the remainder of this experiment.
.4. Remove the wire before applying the potential V
.
To
'
avoid a possible short circuit, a splinter of wood or a ne glass
'
tube may
be used instead of the wire.
-
"
5. With the atomizer six inches or more above and to one side '
_
of the condenser, gently spray some oil toward the holes and put
the cork C, or the cover of gure 1—3, in place. On looking through
.
the microscope, a diused light will be seen at rst which soon
‘
_
thins out.
Then, small individual bright spots, the oil drops,
may
be seen.
In selectihg one of the smaller drops, choose one
which moves very slowly, both up and down. It will then carry
fewen charges and will demonstrate the granular nature of elec—
trici‘ty more clearly. Brownian movement may cause the drop
to waver back and forth a slight amount.
If the drop tends to
drift out of focus, move the microscope as a whole, without
,
_
changing its magnication. If the drifting is excessive, re—level
the condenser plates.
'
.
Oâservaliom.,—6. Read the barometric pressure, p,. at the
beginning and end of the experiment and use the average value.
’
7. Calibrate the microscope scale by observing a standard
'
.
0.1.mm. scale and
-
respond to one division, of the scale (=k).' Be careful not to
:
change the focus of the microscope from now on.
8. Measure the distance of between the inner faces of the con—
Ï
danser plates by. means
of the calibrated microscope.
.
_
9 Record the remaining constants of equation 1—12. The
Nye’s
Oil is 0.92 grams per cubic centimeter.
‘
Thecoeic1ent of
the,_air. may be taken as that at
temperature.
.
__
_
? 10‘-.FOHOW
…Èîrop {as long
possible; —
“ _
;.at least
,
beurreœrdmgthet1mef0rthedroptomoveup(dawn.in the
°fd1V1swnsThetlmeœmwe upmtheelectr1cale1dwl .'
ChangeWheneV€fthedrpgamsarlesewnerm0reelectrons
f
1.
THE CHARGE OF THE ELECTRON
scale divisions to be clearly distinguished. Adjust the focus of the
microscope as a whole and also that of its eyepiece until there is
no parallax between the streak of light and the scale. Do not
change the focus during the remainder of this experiment.
.4. Remove the wire before applying the potential V
.
To
'
avoid a possible short circuit, a splinter of wood or a ne glass
'
tube may
be used instead of the wire.
-
"
5. With the atomizer six inches or more above and to one side '
_
of the condenser, gently spray some oil toward the holes and put
the cork C, or the cover of gure 1—3, in place. On looking through
.
the microscope, a diused light will be seen at rst which soon
‘
_
thins out.
Then, small individual bright spots, the oil drops,
may
be seen.
In selectihg one of the smaller drops, choose one
which moves very slowly, both up and down. It will then carry
fewen charges and will demonstrate the granular nature of elec—
trici‘ty more clearly. Brownian movement may cause the drop
to waver back and forth a slight amount.
If the drop tends to
drift out of focus, move the microscope as a whole, without
,
_
changing its magnication. If the drifting is excessive, re—level
the condenser plates.
'
.
Oâservaliom.,—6. Read the barometric pressure, p,. at the
beginning and end of the experiment and use the average value.
’
7. Calibrate the microscope scale by observing a standard
'
.
0.1.mm. scale and
-
respond to one division, of the scale (=k).' Be careful not to
:
change the focus of the microscope from now on.
8. Measure the distance of between the inner faces of the con—
Ï
danser plates by. means
of the calibrated microscope.
.
_
9 Record the remaining constants of equation 1—12. The
Nye’s
Oil is 0.92 grams per cubic centimeter.
‘
Thecoeic1ent of
the,_air. may be taken as that at
temperature.
.
__
_
? 10‘-.FOHOW
…Èîrop {as long
possible; —
“ _
;.at least
,
beurreœrdmgthet1mef0rthedroptomoveup(dawn.in the
°fd1V1swnsThetlmeœmwe upmtheelectr1cale1dwl .'
ChangeWheneV€fthedrpgamsarlesewnerm0reelectrons
f