Modern Physics, 3rd Edition
Modern Physics, 3rd Edition
3rd Edition
ISBN: 9780534493394
Author: Raymond A. Serway, Clement J. Moses, Curt A. Moyer
Publisher: Cengage Learning
bartleby

Concept explainers

Question
Book Icon
Chapter 4, Problem 6P

(a)

To determine

The radius and the mass of the drop used in the experiment.

(a)

Expert Solution
Check Mark

Answer to Problem 6P

The radius is 1.62×106m_ and the mass is 1.42×1014kg_.

Explanation of Solution

Write the expression for the radius of the oil drop in the Millikan’s experiment.

    a=9ηv2ρg        (I)

Here, η is the viscosity of the liquid, v is the velocity of the oil drop, ρ is the density and g is the acceleration due to gravity.

The mass of the oil drop is given by,

    m=ρV        (II)

Here, V is the volume, m is the mass of the oil drop.

The volume of the oil drop is given by,

    V=43πa3        (III)

Use equation (III) in (II),

    m=ρ(43)πa3        (IV)

The average speed of the oil drop is given as,

    v=ΔyΔt=4.0×103m15.9s=2.52×104m/s

Conclusion:

Substitute 1.81×105kg/ms for η, 2.52×104m/s for v, 800kg/m3 for ρ and 9.81m/s2 for g in equation (I) to find a.

    a=(9(1.81×105kg/ms)(2.52×104m/s)2(800kg/m3)(9.81m/s2))1/2=1.62×106m

Substitute 1.33 for ρ, 1.62×106m for a in equation (IV) to find m.

    m=(1.33)(800kg/m3)(π)(1.62×106m)3=1.42×1014kg

Therefore, the radius is 1.62×106m_ and the mass is 1.42×1014kg_.

(b)

To determine

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)

Expert Solution
Check Mark

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,

    q1=mgE(v+v1)v        (V)

Here, v is the velocity of fall, v is the velocity of rise, E is the electric field, v is the upward terminal speed in the presence of the electric field, v is the downward terminal velocity in the absence of the electric field.

The expression for the electric field is given by,

    E=Vd        (VI)

Conclusion:

Using the times given, the various v can be calculated as,

    v1=4×103m36.0s=1.11×104m/sv2=4×103m17.3s=2.31×104m/s

    v3=4×103m24.0s=1.67×104m/sv4=4×103m11.4s=3.51×104m/s

    v5=4×103m7.54s=5.31×104m/s

The corresponding charges can be written as,

    q1=(6.97×1019C)(2.52+1.11)2.52=10.0×1019Cq2=13.4×1019C

    q3=11.6×1019Cq4=16.7×1019Cq5=21.6×1019C

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)

To determine

The electronic charge from the data.

(c)

Expert Solution
Check Mark

Answer to Problem 6P

The average value is 1.67×1019C_.

Explanation of Solution

To find an integer n1 such that 1.5×1019<qn1<2.0×1019

    q16=1.67×1019Cq28=1.68×1019Cq37=1.66×1019Cq410=1.67×1019C

  q513=1.66×1019C

The amount of charge gained or lost is,

    q2q1=3.4×1019Cq3q1=1.6×1019Cq2q3=1.8×1019Cq4q1=6.7×1019C

    q4q3=5.1×1019Cq4q2=3.4×1019Cq5q1=11.6×1019Cq5q4=4.9×1019C

    q5q4=4.9×1019Cq5q3=10.0×1019C

The integers that yield a value of e between 1.5 and 2.0×1019C.

    q2q12=1.70×1019Cq3q11=1.60×1019Cq2q31=1.80×1019Cq4q14=1.68×1019C

    q4q33=1.70×1019Cq4q22=1.65×1019Cq5q17=1.66×1019Cq5q43=1.63×1019C

    q5q36=1.67×1019C

The average of all values will be 1.67×1019C.

Conclusion:

Therefore, The average value is 1.67×1019C_.

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!
Students have asked these similar questions
••63 SSM www In the circuit of Fig. 27-65, 8 = 1.2 kV, C = 6.5 µF, R₁ S R₂ R3 800 C H R₁ = R₂ = R3 = 0.73 MQ. With C completely uncharged, switch S is suddenly closed (at t = 0). At t = 0, what are (a) current i̟ in resistor 1, (b) current 2 in resistor 2, and (c) current i3 in resistor 3? At t = ∞o (that is, after many time constants), what are (d) i₁, (e) i₂, and (f) iz? What is the potential difference V2 across resistor 2 at (g) t = 0 and (h) t = ∞o? (i) Sketch V2 versus t between these two extreme times. Figure 27-65 Problem 63.
Thor flies by spinning his hammer really fast from a leather strap at the end of the handle, letting go, then grabbing it and having it pull him. If Thor wants to reach escape velocity (velocity needed to leave Earth’s atmosphere), he will need the linear velocity of the center of mass of the hammer to be 11,200 m/s. Thor's escape velocity is 33532.9 rad/s, the angular velocity is 8055.5 rad/s^2. While the hammer is spinning at its maximum speed what impossibly large tension does the leather strap, which the hammer is spinning by, exert when the hammer is at its lowest point? the hammer has a total mass of 20.0kg.
If the room’s radius is 16.2 m, at what minimum linear speed does Quicksilver need to run to stay on the walls without sliding down?  Assume the coefficient of friction between Quicksilver and the wall is 0.236.
Knowledge Booster
Background pattern image
Physics
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, physics and related others by exploring similar questions and additional content below.
Similar questions
SEE MORE QUESTIONS
Recommended textbooks for you
Text book image
Modern Physics
Physics
ISBN:9781111794378
Author:Raymond A. Serway, Clement J. Moses, Curt A. Moyer
Publisher:Cengage Learning
Text book image
Principles of Physics: A Calculus-Based Text
Physics
ISBN:9781133104261
Author:Raymond A. Serway, John W. Jewett
Publisher:Cengage Learning
Text book image
College Physics
Physics
ISBN:9781938168000
Author:Paul Peter Urone, Roger Hinrichs
Publisher:OpenStax College
Text book image
Intro Spectroscopy
Physics
ISBN:9781305221796
Author:PAVIA
Publisher:Cengage
Text book image
University Physics Volume 3
Physics
ISBN:9781938168185
Author:William Moebs, Jeff Sanny
Publisher:OpenStax
Text book image
Physics for Scientists and Engineers with Modern ...
Physics
ISBN:9781337553292
Author:Raymond A. Serway, John W. Jewett
Publisher:Cengage Learning