Download Millikan`s Oil Drop Experiment Worksheet

Millikan’s Oil Drop Experiment Worksheet
1.
Name:
An oil drop with a mass of 4.80 x 10-16 kg is suspended between two horizontal parallel plates that
are 6.00 cm apart. If the potential difference between the plates is 5.90 x 102 V, how many excess
electrons does the oil drop carry?
Ans: 3
2.
An oil drop with a mass of 7.20 x 10-16 kg is suspended between two horizontal parallel plates that
have an electric field strength of 2.20 x 104 V/m, what is the magnitude of the charge on the oil
drop?
Ans: 3.21 x 10-19 C
3.
During a Millikan oil drop experiment, a student records the weight of five different oil drops. A
record is also made of the electric field intensity necessary to hold each drop stationary between
the two horizontal plates:
Weight ( x 10-14 N)
1.7
5.6
6.1
2.9
4.0
Electric Field (x 105 N/C)
1.1
3.5
3.8
1.8
2.5
The electric field is the manipulated variable in this experiment. Plot the graph showing the
relationship between the weight and the electric field.
Use only your graph, determine the elementary charge.
Ans: ( (1.6  0.1) x 10-19 C
4.
An oil droplet (q = 5e) is suspended between two parallel charged plates (V = 175 V). If an oil
droplet of the same mass but a charge of 3e is to be suspended between the same plates, what
potential difference would be needed?
Ans: 292 V
5.
An oil drop is suspended between two parallel charged plates. Calculate the magnitude of the
charge on the oil droplet given the following:
Radius of the oil drop:
Density of the oil:
Distance between the plates:
Potential difference between the plates:
4.2 x 10-6 m
7.8 X 102 g/m3
2.0 cm
99 V
Ans: 4.8 x 10-19 C