PROBLEMS
1—1. What voltage is needed to balance an oil drop carrying 5 elec—
trons when located between the plates of a condenser Which are 5 mm.
apart? The mass of the oil drop is 3.119 X 10“13 gram.
(19.2 volts)
1—2. What is the velocity of fall of an oil drop of density 0.98 and
radius 10‘4 cm. in air of visCosity 0.0001826 and pressure 76 cm. of
,
mercury.
Use both the c0rrected and uncorrected laws of fall.
(Corrected 0.0]26 cm./sec; Uncorrected 0.01] 7 cm./sec.)
1—3. 31.5 volts applied to two parallel plates 1 cm. apart give a
charged“ oil drop between them an upward velocity of 10 divisions in
10 seconds (50 divisions = 1 mm.).
The drop falls freely under gravity
With a velocity of 10 divisions in 100 seconds. The coefcient of viscosity
'
of air = 0.00018.
Density of the drop = 0.9. Neglect the density of air.
Pressure = 76 cm. Hg. How many electrons does the drop carry? (one)
1—4. In a determination of Avogadro’s number N from Brownian movements, the average-squared-distance of Brownian displacement through
‘
which the particle moves in 30 seconds is found to be 3.70 >< 10‘5,cm.
The temperature = 21° C.; the pressure = 74.4 cm.; the density of the
_
oil = 0.92 gr./cm.3; and the average time to fall freely over a distance of
0.944 mm. is found to be 100.8 sec.
Find N.
,
…
'
1—5. The angle 0 through which an X—ray beam (CuK… line = 1.54 Â')
is diffracted from a crystal
rock salt (molecular weight = 58.45,
density = 2.163 g./cc.) is 15° 54' (rst order). Find the value of 6.
2—1.
volts are applied to the plate of atwo-electrode tube. What
-
is the velocity of the electrons when they reach the plate?
'
,
'
'
'
,
_
(1.88 X 109 cm./sec.) .
,
_2—2. What acéeleratirig voltage is needed to give cathode particles
;
a velocity of 3.763 >< 109 cm. per second?
.
" _
(4004 volts)
’
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two electrons acceler‘ated
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1—1. What voltage is needed to balance an oil drop carrying 5 elec—
trons when located between the plates of a condenser Which are 5 mm.
apart? The mass of the oil drop is 3.119 X 10“13 gram.
(19.2 volts)
1—2. What is the velocity of fall of an oil drop of density 0.98 and
radius 10‘4 cm. in air of visCosity 0.0001826 and pressure 76 cm. of
,
mercury.
Use both the c0rrected and uncorrected laws of fall.
(Corrected 0.0]26 cm./sec; Uncorrected 0.01] 7 cm./sec.)
1—3. 31.5 volts applied to two parallel plates 1 cm. apart give a
charged“ oil drop between them an upward velocity of 10 divisions in
10 seconds (50 divisions = 1 mm.).
The drop falls freely under gravity
With a velocity of 10 divisions in 100 seconds. The coefcient of viscosity
'
of air = 0.00018.
Density of the drop = 0.9. Neglect the density of air.
Pressure = 76 cm. Hg. How many electrons does the drop carry? (one)
1—4. In a determination of Avogadro’s number N from Brownian movements, the average-squared-distance of Brownian displacement through
‘
which the particle moves in 30 seconds is found to be 3.70 >< 10‘5,cm.
The temperature = 21° C.; the pressure = 74.4 cm.; the density of the
_
oil = 0.92 gr./cm.3; and the average time to fall freely over a distance of
0.944 mm. is found to be 100.8 sec.
Find N.
,
…
'
1—5. The angle 0 through which an X—ray beam (CuK… line = 1.54 Â')
is diffracted from a crystal
rock salt (molecular weight = 58.45,
density = 2.163 g./cc.) is 15° 54' (rst order). Find the value of 6.
2—1.
volts are applied to the plate of atwo-electrode tube. What
-
is the velocity of the electrons when they reach the plate?
'
,
'
'
'
,
_
(1.88 X 109 cm./sec.) .
,
_2—2. What acéeleratirig voltage is needed to give cathode particles
;
a velocity of 3.763 >< 109 cm. per second?
.
" _
(4004 volts)
’
2—3COInpütethe ratio of the masses
two electrons acceler‘ated
_,Ï
‘
=
‘
(1-ÛÛÔ)‘_ - —îl j î
Ï 2—4Fmdthestfength tl>Ïf‘t‘hc magnefië‘eld ccsssary ,t0 causé an-d°—a f
,_
tronofenergy1000
in ajc_ircular p ath"
"Ï—'
ndnrnytun1tn fengy1000thmovm