
Concept explainers
(a)
The radius and the mass of the drop used in the experiment.
(a)

Answer to Problem 6P
The radius is
Explanation of Solution
Write the expression for the radius of the oil drop in the Millikan’s experiment.
Here,
The mass of the oil drop is given by,
Here,
The volume of the oil drop is given by,
Use equation (III) in (II),
The average speed of the oil drop is given as,
Conclusion:
Substitute
Substitute
Therefore, the radius is
(b)
The charge on each drop and show that the charge is quantized by considering both the size of each charge and the amount of charge gained when the rise time changes.
(b)

Answer to Problem 6P
It is shown that the charge is quantized by considering both the size of each charge and the amount of charge gained when the rise time changes.
Explanation of Solution
The charge on the droplet is given by,
Here,
The expression for the electric field is given by,
Conclusion:
Using the times given, the various
The corresponding charges can be written as,
Therefore, It is shown that the charge is quantized by considering both the size of each charge and the amount of charge gained when the rise time changes.
(c)
The electronic charge from the data.
(c)

Answer to Problem 6P
The average value is
Explanation of Solution
To find an integer
The amount of charge gained or lost is,
The integers that yield a value of
The average of all values will be
Conclusion:
Therefore, The average value is
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Chapter 4 Solutions
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