Intro to 408 and Lecture 1
Welcome to General Physics II Physics 408 Please make sure you get a Syllabus Physics 408 will cover some of the general physics topics, which are the basis of all other science and engineering fields: Waves, Heat & Kinetic Theory, Thermodynamics, Electricity, Circuits, Magnetism. Course website: http://physics.unh.edu/phys408 If you can not read this, you are sitting too far in the back!
Physics 408 is… • More challenging and time consuming than 407. • Will use more mathematics than 407. (Math 426 is a co-requisite) • Will cover more different topics than 407.
Physics 408 Website Announcements
(Make sure you check your email!)
Syllabus Contacts
Remote Pad • Used to give in class concept quizzes (yes they are graded, yes they count) • ALWAYS bring it to lecture. • Buy at the bookstore (if you have one from last semester, buy a new registration code.)
• Register at einstuction.com with class key: i2404g60 (see website for instructions) • Will start using the pad NEXT WEEK
WebAssign • We will do homework on WebAssign. • Please sign in TODAY and do “Intro” assignment. • Homework Week: – 3x Reading Assignment Due before lecture (WebAssign) – 1x Homework Problems Due midnight Thursdays. (WebAssign + Hand-in)
– 1x Laboratory Report Due one week after lab. (Hand-in)
• First Reading Assignment on WebAssign: Monday 26th • First Homework Due on WebAssign: Thursday 29th
WebAssign Access You will have access immediately, but for only 14 days. You need to buy an access card for WebAssign (at the bookstore, or at the WebAssign website). Some of you may already have such a card, which came with your book. Without this, you cannot do your homework….
Lectures • We will cover the most important parts of the material. • Please do your reading assignment before lecture (WebAssign). • Material in reading assignment will be on Exam, not only material covered in lecture. • Always bring your “clicker” for class participation.
Recitations • Recitations are there to help you! • Yes, they are mandatory. • Typical recitation: – Question/Answer period. – Group Problem
• Please come on time …
Laboratory • This is where you get some hands-on experience. • ALL labs must be done to pass the course! (There are special weeks scheduled for make-up labs.)
• Lab reports are due one week after the Lab. • Labs will start on the week February 3rd. • I have asked to Lab TA’s to take a picture of each of you during the first lab, so that I may get to know you all better.
Staff & Office Hours Office hours are subject to change. Check the Web. Call or email the professor if you want to make an appointment. Instructor
Office
Phone
E-mail
Prof. Maurik Holtrop Main Lecture
DeMeritt 202 862-2019 [email protected] hours: Wed 3-4pm
Prof. Jim Raeder Rec #2: Th 9:40-11am
Morse Hall 245G 862-3412 [email protected] hours: Wed & Fri 9-11am
Prof. Silas Beane DeMeritt 209E 862-2720 [email protected] Rec #3: Th 11:10-12:30 hours: Thurs 12:30-1:30 am Prof. John Dawson Rec #1: Th 2:10-3:30 pm
DeMeritt 204
862-1960 [email protected]
hours:T 3-4:30, F 1:30-3
Email:
ALL
EXAMS • Fixed Schedule • No Make-ups, No exceptions. • No exam will be dropped. Exam 1 Exam 2 Exam 3 Final
Thurs Feb 19 7:10 - 9pm Thurs Mar 25 7:10 - 9pm Tues Apr 13 7:10 - 9pm TBD TBD
James 303 James 303 James 303 TBD
Waves & Thermo CH 17-21 Electrostatics Ch 22-25 Currents & Circuits Ch 26-28 Magnetism Ch 29- 33
Grading • Everything counts… 4 1-hour exams
50%
No exam dropped!
Laboratory
15%
ALL Labs required for pass!
Recitation Problems
10%
Homework + Reading
15%
Lecture Participation.
10%
Total
100%
• Total score < 60% is a fail.
Etiquette / Honor Code • No Cheating! – Don’t copy homework or lab reports. – Don’t look at another paper during exam, or talk, or read. – Don’t use more than one clicker.
• Come on time, don’t leave early. • Respect each other (no laughing at a question). • Don’t talk or disrupt the class.
Physics 407 • I expect you to have remembered the material from Physics 407. • A “lightning overview” of Physics 407 can be found on the website under “Lectures”.
Transverse Traveling Waves Chapter 17, Sections 1Æ6 Mechanical waves, which we will cover in Chapter 17 are an important topic for ME and Civil Engineers for the proper construction of buildings, bridges, cars ... Waves are important in all other science and engineering fields too. EE major will see this in radio, microwave & radar technology. Chemistry, Medical in NMR, X-ray techniques. CS in audio/video applications and file compression techniques. There are too many examples to list here!
WAVES Types of Waves: • Mechanical: Waves travel through a material, wave properties are governed by Newton’s Laws. EG: Sound, Ocean Waves, Guitar String, … • Electromagnetic Waves: Waves are oscillations of the E and B fields, which are governed by Maxwell’s Equations. • Matter Waves: Particles also behave as waves, but it is not so clear what it is that is “waving”. Governed by Quantum Mechanics. • Gravity Waves: Yes, gravity also has waves. They are governed by General Relativity, Einstein’s formulation of gravity.
Two Classifications of Waves: • Transverse Waves: The movement of the material is perpendicular to the direction in which the wave travels: Ocean waves, Guitar String. • Longitudinal Waves: The movement of the material is along the direction in which the wave travels: Sound Î Chapter 18 • Note that while the MATERIAL of a wave moves back and forth, the wave itself moves onward.
Equations for a Transverse Wave. Step by Step: Harmonic Oscillator:
y (t , x = 0) = ym sin (ωt + φ0 )
Another Harmonic Oscillator:
y (t , x = x1 ) = ym sin (ωt − kx1 + φ0 )
Equation for a transverse traveling wave:
y(t, x) =
ym sin kx − ωt + φ0
Wave Equation Explained
y(t, x) =
ym sin kx − ωt + φ0
The different parts of this formula are:
y (t , x)
Displacement. I.e. the wave’s movement is in the Y direction.
ym
The Amplitude.
sin ( kx − ωt + φ0 )
( kx − ωt + φ0 ) ω , k , φ0
Oscillating term. (All harmonic movements must have this.) The “Phase”.
φ0
This is confusing, since
is called the phase constant.
Angular frequency, Wave number, and phase constant.
Graph of Wave vs x. ym=Amplitude
y
λ = Wave Length
3 2 1 0 -1 -2 -3 0
2
4
6
8
10
12
x
Graph of Wave vs. t y
ym=Amplitude
T = Wave Period
3 2 1 0 -1 -2 -3 0
2
4
6
8
10
t
12
Definition of terms for wave k=
2π
λ
2π ω= T 1 ω f = = T 2π
= Angular wave number.
= Angular Frequency.
= Frequency.
Speed of a Wave I y ( x, t ) = ym sin ( kx − ωt + φ0 )
kx − ωt + φ = π 2 ∂x v= ∂t
∂x ω k −ω + 0 = 0 ⇒ v = ∂t k v=
ω k
=
λ
T
=λ f
Transverse Velocity and Acceleration y ( x, t ) = ym sin ( kx − ωt + φ0 )
∂y( x, t ) ∂ u= = ym sin ( kx − ωt + φ ) = ∂t ∂t = −ω ym cos ( kx − ωt + φ )
(
)
(
∂u ∂ 2 y ( x, t ) 2 ay = = = −ω ym sin kx − ωt + φ 2 ∂t ∂t
)
Speed of a Wave II The speed is
dx v= dt
v has dimensions of length/time.
String has linear mass density with dimensions of mass/length. The tension,
τ
µ = ml
in the string is a Force Î mass*length/time2.
We want to get length/time, and there is only one way to do this!
τ
µ
has dimensions of length2/time2, so:
τ v= µ There could be a dimensionless constant, but in this case that is actually equal to 1.
Speed of a Wave on a String III τL
mass = µdx
τR dx
Speed of a Wave on a String III τL F=τL+τR
τR
Speed of a Wave on a String III G G G F = τ L +τ R Fy = τ Ly −τ Ry
∂ 2 y ( x, t ) Fy = ma y = µ dx ∂t 2 τ Lx = τ Ly ≈ τ
τ τ Fy = τ Ly − Ry τ Lx τ Rx
∂ 2 y ( x, t ) ∂y ( x, t ) ∂y ( x, t ) µ dx =τ − ⇒ 2 ∂ ∂ x x ∂t L R ∂ 2 y ( x, t ) τ ∂y ( x, t ) ∂y ( x, t ) 1 = − ∂x R dx µ ∂x L ∂t 2
∂y ( x, t ) ∂y ( x, t ) − = τ x x ∂ ∂ L R
Wave Equation
∂ 2 y ( x, t ) τ ∂ 2 y ( x, t ) 0 − = 2 µ ∂x ∂t 2
Speed of a Wave on a String III ∂ 2 y ( x, t ) τ ∂ 2 y ( x, t ) − =0 2 2 µ ∂x ∂t
y ( x, t ) = ym sin ( kx − ωt + φ0 ) −ω ym sin ( kx − ωt + φ ) 2
+ τ k 2 y sin µ m
2 τ ω τ ω τ 2 2 ω = k ⇒ 2 = ⇒v= = µ µ µ k k
=0 kx − ω t + φ ( )
REMEMBER: • Get & Register Clicker • Sign onto WebAssign • Read Chapter 17!!
Physics 408 is… • More challenging and time consuming than 407. • Will use more mathematics than 407. (Math 426 is a co-requisite) • Will cover more different topics than 407.
Physics 408 Website Announcements
(Make sure you check your email!)
Syllabus Contacts
Remote Pad • Used to give in class concept quizzes (yes they are graded, yes they count) • ALWAYS bring it to lecture. • Buy at the bookstore (if you have one from last semester, buy a new registration code.)
• Register at einstuction.com with class key: i2404g60 (see website for instructions) • Will start using the pad NEXT WEEK
WebAssign • We will do homework on WebAssign. • Please sign in TODAY and do “Intro” assignment. • Homework Week: – 3x Reading Assignment Due before lecture (WebAssign) – 1x Homework Problems Due midnight Thursdays. (WebAssign + Hand-in)
– 1x Laboratory Report Due one week after lab. (Hand-in)
• First Reading Assignment on WebAssign: Monday 26th • First Homework Due on WebAssign: Thursday 29th
WebAssign Access You will have access immediately, but for only 14 days. You need to buy an access card for WebAssign (at the bookstore, or at the WebAssign website). Some of you may already have such a card, which came with your book. Without this, you cannot do your homework….
Lectures • We will cover the most important parts of the material. • Please do your reading assignment before lecture (WebAssign). • Material in reading assignment will be on Exam, not only material covered in lecture. • Always bring your “clicker” for class participation.
Recitations • Recitations are there to help you! • Yes, they are mandatory. • Typical recitation: – Question/Answer period. – Group Problem
• Please come on time …
Laboratory • This is where you get some hands-on experience. • ALL labs must be done to pass the course! (There are special weeks scheduled for make-up labs.)
• Lab reports are due one week after the Lab. • Labs will start on the week February 3rd. • I have asked to Lab TA’s to take a picture of each of you during the first lab, so that I may get to know you all better.
Staff & Office Hours Office hours are subject to change. Check the Web. Call or email the professor if you want to make an appointment. Instructor
Office
Phone
Prof. Maurik Holtrop Main Lecture
DeMeritt 202 862-2019 [email protected] hours: Wed 3-4pm
Prof. Jim Raeder Rec #2: Th 9:40-11am
Morse Hall 245G 862-3412 [email protected] hours: Wed & Fri 9-11am
Prof. Silas Beane DeMeritt 209E 862-2720 [email protected] Rec #3: Th 11:10-12:30 hours: Thurs 12:30-1:30 am Prof. John Dawson Rec #1: Th 2:10-3:30 pm
DeMeritt 204
862-1960 [email protected]
hours:T 3-4:30, F 1:30-3
Email:
ALL
EXAMS • Fixed Schedule • No Make-ups, No exceptions. • No exam will be dropped. Exam 1 Exam 2 Exam 3 Final
Thurs Feb 19 7:10 - 9pm Thurs Mar 25 7:10 - 9pm Tues Apr 13 7:10 - 9pm TBD TBD
James 303 James 303 James 303 TBD
Waves & Thermo CH 17-21 Electrostatics Ch 22-25 Currents & Circuits Ch 26-28 Magnetism Ch 29- 33
Grading • Everything counts… 4 1-hour exams
50%
No exam dropped!
Laboratory
15%
ALL Labs required for pass!
Recitation Problems
10%
Homework + Reading
15%
Lecture Participation.
10%
Total
100%
• Total score < 60% is a fail.
Etiquette / Honor Code • No Cheating! – Don’t copy homework or lab reports. – Don’t look at another paper during exam, or talk, or read. – Don’t use more than one clicker.
• Come on time, don’t leave early. • Respect each other (no laughing at a question). • Don’t talk or disrupt the class.
Physics 407 • I expect you to have remembered the material from Physics 407. • A “lightning overview” of Physics 407 can be found on the website under “Lectures”.
Transverse Traveling Waves Chapter 17, Sections 1Æ6 Mechanical waves, which we will cover in Chapter 17 are an important topic for ME and Civil Engineers for the proper construction of buildings, bridges, cars ... Waves are important in all other science and engineering fields too. EE major will see this in radio, microwave & radar technology. Chemistry, Medical in NMR, X-ray techniques. CS in audio/video applications and file compression techniques. There are too many examples to list here!
WAVES Types of Waves: • Mechanical: Waves travel through a material, wave properties are governed by Newton’s Laws. EG: Sound, Ocean Waves, Guitar String, … • Electromagnetic Waves: Waves are oscillations of the E and B fields, which are governed by Maxwell’s Equations. • Matter Waves: Particles also behave as waves, but it is not so clear what it is that is “waving”. Governed by Quantum Mechanics. • Gravity Waves: Yes, gravity also has waves. They are governed by General Relativity, Einstein’s formulation of gravity.
Two Classifications of Waves: • Transverse Waves: The movement of the material is perpendicular to the direction in which the wave travels: Ocean waves, Guitar String. • Longitudinal Waves: The movement of the material is along the direction in which the wave travels: Sound Î Chapter 18 • Note that while the MATERIAL of a wave moves back and forth, the wave itself moves onward.
Equations for a Transverse Wave. Step by Step: Harmonic Oscillator:
y (t , x = 0) = ym sin (ωt + φ0 )
Another Harmonic Oscillator:
y (t , x = x1 ) = ym sin (ωt − kx1 + φ0 )
Equation for a transverse traveling wave:
y(t, x) =
ym sin kx − ωt + φ0
Wave Equation Explained
y(t, x) =
ym sin kx − ωt + φ0
The different parts of this formula are:
y (t , x)
Displacement. I.e. the wave’s movement is in the Y direction.
ym
The Amplitude.
sin ( kx − ωt + φ0 )
( kx − ωt + φ0 ) ω , k , φ0
Oscillating term. (All harmonic movements must have this.) The “Phase”.
φ0
This is confusing, since
is called the phase constant.
Angular frequency, Wave number, and phase constant.
Graph of Wave vs x. ym=Amplitude
y
λ = Wave Length
3 2 1 0 -1 -2 -3 0
2
4
6
8
10
12
x
Graph of Wave vs. t y
ym=Amplitude
T = Wave Period
3 2 1 0 -1 -2 -3 0
2
4
6
8
10
t
12
Definition of terms for wave k=
2π
λ
2π ω= T 1 ω f = = T 2π
= Angular wave number.
= Angular Frequency.
= Frequency.
Speed of a Wave I y ( x, t ) = ym sin ( kx − ωt + φ0 )
kx − ωt + φ = π 2 ∂x v= ∂t
∂x ω k −ω + 0 = 0 ⇒ v = ∂t k v=
ω k
=
λ
T
=λ f
Transverse Velocity and Acceleration y ( x, t ) = ym sin ( kx − ωt + φ0 )
∂y( x, t ) ∂ u= = ym sin ( kx − ωt + φ ) = ∂t ∂t = −ω ym cos ( kx − ωt + φ )
(
)
(
∂u ∂ 2 y ( x, t ) 2 ay = = = −ω ym sin kx − ωt + φ 2 ∂t ∂t
)
Speed of a Wave II The speed is
dx v= dt
v has dimensions of length/time.
String has linear mass density with dimensions of mass/length. The tension,
τ
µ = ml
in the string is a Force Î mass*length/time2.
We want to get length/time, and there is only one way to do this!
τ
µ
has dimensions of length2/time2, so:
τ v= µ There could be a dimensionless constant, but in this case that is actually equal to 1.
Speed of a Wave on a String III τL
mass = µdx
τR dx
Speed of a Wave on a String III τL F=τL+τR
τR
Speed of a Wave on a String III G G G F = τ L +τ R Fy = τ Ly −τ Ry
∂ 2 y ( x, t ) Fy = ma y = µ dx ∂t 2 τ Lx = τ Ly ≈ τ
τ τ Fy = τ Ly − Ry τ Lx τ Rx
∂ 2 y ( x, t ) ∂y ( x, t ) ∂y ( x, t ) µ dx =τ − ⇒ 2 ∂ ∂ x x ∂t L R ∂ 2 y ( x, t ) τ ∂y ( x, t ) ∂y ( x, t ) 1 = − ∂x R dx µ ∂x L ∂t 2
∂y ( x, t ) ∂y ( x, t ) − = τ x x ∂ ∂ L R
Wave Equation
∂ 2 y ( x, t ) τ ∂ 2 y ( x, t ) 0 − = 2 µ ∂x ∂t 2
Speed of a Wave on a String III ∂ 2 y ( x, t ) τ ∂ 2 y ( x, t ) − =0 2 2 µ ∂x ∂t
y ( x, t ) = ym sin ( kx − ωt + φ0 ) −ω ym sin ( kx − ωt + φ ) 2
+ τ k 2 y sin µ m
2 τ ω τ ω τ 2 2 ω = k ⇒ 2 = ⇒v= = µ µ µ k k
=0 kx − ω t + φ ( )
REMEMBER: • Get & Register Clicker • Sign onto WebAssign • Read Chapter 17!!
