Due to Monday Holiday (Presidents Day 2/18), 2/14 Thursday DL Section (1,3,4) cancelled. (DL Section 7,10 meet as normal) 2/15 Friday DL Section 2,5,6.

Slides:



Advertisements
Similar presentations
Chapter 16 Section 1.
Advertisements

Unit 7 Energy.  Energy is the ability to do work or cause change. I can work…but I won’t.
Molecular Bonds Molecular Spectra Molecules and Solids CHAPTER 10 Molecules and Solids Johannes Diderik van der Waals (1837 – 1923) “You little molecule!”
Lecture # 3 Cassandra Paul Physics Summer Session II 2008.
Lecture # 5 Cassandra Paul Physics 7A Summer Session II 2008.
Pre-Lecture Quiz: – MasteringAstronomy Ch15 pre-lecture quiz due February 17 Homework: – MasteringAstronomy.
Chapter 6 The States of Matter
Knight: Chapter 18 The Micro/Macro Connection
Lecture # 7 Cassandra Paul Physics 7A Summer Session II 2008.
Lecture #8 Cassandra Paul Physics 7A Summer Session II 2008.
Physics 7A – Lecture 5 Winter 2008 Prof. Robin D. Erbacher 343 Phy/Geo Bldg Prof. Robin D. Erbacher 343 Phy/Geo Bldg
Lecture #4 Cassandra Paul Physics 7A Summer Session II 2008.
New location for the Course website 08WinCD/7A_2008WinCD.html Also accessible from:
Quiz information on the course website Include : Quiz answers (posted by ~5pm Tuesdays) Quiz problems Quiz rubrics (posted by 5pm following Tuesdays) Quiz.
Applications of Normal Modes Physics 213 Lecture 20.
Quiz 2 8:30-8:50am TODAY Closed book Next lecture January 29 Quiz 3 will cover the material from today’s lecture, FNT’s from DLM 3, material from DLM4.
Quiz 1 8:30-8:50am TODAY Closed book 7A Final March 18, Tuesday 10:30am-12:30pm No makeup final/quiz Chapter 0 = introductory material at the beginning.
Lecture #6 Physics 7A Cassandra Paul Summer Session II 2008.
Quiz 4 8:30-8:50am TODAY Have your calculator ready. Cell phone calculator NOT allowed. Closed book Quiz 1 & 2 grade available on the course website (last.
Quiz 7 8:30-8:50am TODAY Have your calculator ready. Cell phone calculator NOT allowed. Closed book Quiz 3 Re-evaluation Request Due this Thursday, 2/28.
Physics 7A – Lecture 7 Winter 2009
Last Lecture Quiz 5,6,7 Re-evaluation Request Due at the time of Final Turn in you original Quiz along with the Re-evaluation Request Form. Note: It is.
Physics 7A – Review Winter 2008 Prof. Robin D. Erbacher 343 Phy/Geo Bldg Prof. Robin D. Erbacher 343 Phy/Geo Bldg
Lecture # 9 Physics 7A Summer Session II Evaluations First You get 15 minutes to do Evaluations This Evaluation is for Cassandra the Lecturer You.
Discover PHYSICS for GCE ‘O’ Level Science
Learning outcomes Compare the properties of solids, liquids and gases
Physics 7A – Lecture 4 Winter 2008 Prof. Robin D. Erbacher 343 Phy/Geo Bldg Prof. Robin D. Erbacher 343 Phy/Geo Bldg
States of Matter and Phase Changes. Kinetic Theory of Matter: Matter is made of particles that are in constant motion – Describes how close together the.
The following question was posed to the physicist Richard Feynman, winner of the Nobel Prize for his work on the theory of quantum electrodynamics: If,
"You can dance anywhere, even if only in your heart." ~Unknown "If dancing were any easier it would be called football." ~anonymous.
Forms of Energy  Kinetic Energy – due to the movement of an object. As the blocks move they lose potential energy but it is converted to kinetic Kinetic.
Physics 7A – Lecture 6 Winter 2008 Prof. Robin D. Erbacher 343 Phy/Geo Bldg Prof. Robin D. Erbacher 343 Phy/Geo Bldg
Calcium carbonate (marble) hydrochloric acid carbon dioxide.
Wednesday, Nov. 20 th : “A” Day Thursday, Nov. 21 st : “B” Day Agenda  Homework questions/collect  Section 11.1 Quiz  Start Section 11.2: “Intermolecular.
Chapter 12 Liquids, Solids, and Intermolecular Forces.
5/19 do now – on a new sheet A spark timer is used to record the position of a lab cart accelerating uniformly from rest. Each 0.10 second, the timer marks.
PHYSICAL BEHAVIOR OF MATTER
States of Matter Section ity/states_of_matter/ ity/states_of_matter/
From Last Time: Electric field of a single charge Electric field from multiple charges Superposition Ex: calculate electric field of dipole Oct. 1, 2009Physics.
Regents Chemistry   Anything that has mass and takes up space  3 states/phases of matter  Solid  Liquid  Gas Lesson 1:What is matter?
Chemical Interactions Vocabulary. Investigation #4 Kinetic Energy.
Chapter 8 Potential Energy. Potential energy is the energy associated with the configuration of a system of objects that exert forces on each other This.
Potential Energy ~March 1, 2006.
Chapter 9- The States of Matter u Gases indefinite volume and shape, low density. u Liquids definite volume, indefinite shape, and high density. u Solids.
1.WHAT ARE THE DIFFERENCES BETWEEN SOLIDS, LIQUIDS AND GASES? 2.What are Phase changes? TODAY IN PHYSICAL SCIENCE.
States of Matter. What are the three states of matter?
1 Solids, Liquids & Gases. 2 CAN YOU SEE? macroscopicmicroscopic.
The Plan… May 2013 Start Chapter 7 (Kinetic Molecular Theory) We’re on a roll! Section 7.1 “States of Matter” Lecture & Worksheet Worksheet due.
ENERGY Two main types -- kinetic and potential. KINETIC ENERGY Energy of motion Increases as mass increases Increases as speed increases.
Unit 8: Temperature and Matter I Self Learning Package Click here to proceed to next page.
Chapter 12 Thermal Energy.
Chapter #12 States of Matter Inter-particle Forces.
7.2 Temperature and the Phases of Matter
Ch. 13 States of Matter 13.1 Nature of Gases. I. Kinetic Theory A. Kinetic energy (K.E.): energy related to motion B. Kinetic theory assumptions about.
What is mass? TRUE or FALSE? An crystalline solid has a distinct melting point.
 Solid  Liquid  Gas  Plasma  Solid  Liquid  Gas  Plasma.
Thermodynamics Phases (states) of Matter & Latent Heat States of Matter.
Thermal Energy That’s so hot.. All matter is made of tiny little particles (atoms and molecules) All matter is made of tiny little particles (atoms and.
States of Matter Section ity/states_of_matter/ ity/states_of_matter/
Chapter 9 Heat. Temperature  Temperature is proportional to the kinetic energy of atoms and molecules.  Internal energy is the energy of a substance.
Contact forces. “If, in some cataclysm ( 大灾难 ), all of scientific knowledge were to be destroyed, and only one sentence passed on to the next generations.
PHYSICS 197 Section 1 Chapter C9 Potential Energy Graphs
Intermolecular Forces
Thermal Properties of Materials
EDEXCEL Topic 14 PARTICLE MODEL
Friction and Thermal Energy
Energy Goal: 6.P.3 Understand characteristics of energy transfer and interactions of matter and energy.
Kinetic energy of particles, is proportional to how fast they vibrate
Energy exists in different forms.
Energy Goal: 6.P.3 Understand characteristics of energy transfer and interactions of matter and energy.
Presentation transcript:

Due to Monday Holiday (Presidents Day 2/18), 2/14 Thursday DL Section (1,3,4) cancelled. (DL Section 7,10 meet as normal) 2/15 Friday DL Section 2,5,6 cancelled.

Quiz :20am TODAY Have your calculator ready. Cell phone calculator NOT allowed. Closed book Quiz 1 Re-evaluation Request Due this Thursday, 2/14. Quiz 2 Re-evaluation Request Due next Thursday, 2/21. Turn in you original Quiz along with the Re-evaluation Request Form. Note: It is possible for your grade to be lowered after the re-evaluation. Quiz 3 info (grades, ave score) will be posted this week. Quiz 4 graded, scores being recorded. Next lecture February 19 Quiz 6 will cover the material from today’s lecture (excluding equipartition) and material from DLM9 and 10, excluding FNTs for DLM11.

What is the world made of? What holds the world together? Where did the universe come from?

What is the world made of? What holds the world together? Where did the universe come from? Particle Model of Matter

Normal Matter : Particles Bouncing Around! Understand the particulate nature of matter

How big(small) is an atom, anyways?

1 or 2 x m = 1 or 2Å (Angstrom) in radius

How big(small) is an atom, anyways? 1 or 2 x m = 1 to 2Å (Angstrom) in radius

Normal Matter : Particles Bouncing Around! Model Bonded Atoms as Masses on Spring ~ two atomic size particles interacting via“pair-wise potential”

Richard P. Feynman... I believe it is the atomic hypothesis... that all things are made of atoms--little particles that move around in perpetual motion, attracting each other when they are a little distance apart, but repelling upon being squeezed into one another... If all scientific information were to be lost, these would be the most valuable ideas to pass on to future generations. R.P. Feynman, Physics Nobel Laureate in 1965

r PE Distance between the atoms Repulsive: Atoms push apart as they get too close “pair-wise potential” a.k.a. Lennard-Jones Potential Flattening: atoms have negligible forces at large separation.

Displacement from equilibrium y[+][-] PE mass-spring

Displacement from equilibrium y[+][-] PE mass-spring Question: If the mass is displaced upwards, the following is true: a)The dot moves up and to the right, and the force vector points to the left. b)The dot moves up and to the right, and the force vector points to the right. c)The dot moves up and to the left, and the force vector points to the right. d)None of the above.

Displacement from equilibrium y[+][-] direction of force yy PE mass-spring

Displacement from equilibrium y[+][-] direction of force PE mass-spring

Displacement from equilibrium y[+][-] PE mass-spring On this side force pushes up On this side force pushes down Equilibrium Forces from potentials point in direction that (locally) lowers PE

Displacement from equilibrium y[+][-] PE mass-spring Equilibrium Potential Energy curve of a spring:  PE = (1/2) k (  x) 2 W (work) =  PE =F ||  x Force = -  PE /  x = - k x

Displacement from equilibrium y[+][-] PE mass-spring Equilibrium ~Force Potential Energy curve of a spring:  PE = (1/2) k (  x) 2 W (work) =  PE =F ||  x Force = -  PE /  x = - k x Force is always in direction that decreases PE Force is related to the slope -- NOT the value of PE The steeper the PE vs r graph, the larger the force |F|=|d(PE)/dr|

r PE Distance between the atoms Repulsive: Atoms push apart as they get too close “pair-wise potential” a.k.a. Lennard-Jones Potential Flattening: atoms have negligible forces at large separation.

PE KE E tot Separation (x m) Energy (x J)

Example H 2 O Particle Model of E bond Particle Model of E thermal What is E bond in terms of KE and PE of individual atom (atom pair)? What is E thermal in terms of KE and PE of individual atom (atom pair)?

E bond for a substance is the amount of energy required to break apart “all” the bonds i.e. we define E bond = 0 when all the atoms are separated The bond energy of a large substance comes from adding all the potential energies of particles at their equilibrium positions. E bond = ∑ all pairs (PE pair-wise ) A useful approximation of the above relation is, E bond ~ -(total number of nearest neighbor pairs)x(  ) => E bond of the system is determined by both the depth of the pair-wise potential well and the number of nearest-neighbors. Particle Model of E bond

A pair of atoms are interacting via a atom-atom potential. Only these two atoms are around. In two different situations, the pair have a different amount of total energy. In which situation is E tot greater? a) Situation A has a greater E tot b) Situation B has a greater E tot c) Both have the same E tot d) Impossible to tell A B

A pair of atoms are interacting via a atom-atom potential. Only these two atoms are around. In two different situations, the pair have a different amount of total energy. In which situation is E tot greater? a) Situation A has a greater E tot A B

A pair of atoms are interacting via a atom-atom potential. Only these two atoms are around. In two different situations, the pair have a different amount of total energy. In which situation is E tot greater? b) Situation B has a greater E tot A B

A pair of atoms are interacting via a atom-atom potential. Only these two atoms are around. In two different situations, the pair have a different amount of total energy. In which situation is E thermal greater? a) Situation A has a greater E thermal b) Situation B has a greater E thermal c) Both have the same E thermal d) Impossible to tell A B

A pair of atoms are interacting via a atom-atom potential. Only these two atoms are around. In two different situations, the pair have a different amount of total energy. In which situation is E thermal greater? a) Situation A has a greater E thermal b) Situation B has a greater E thermal c) Both have the same E thermal d) Impossible to tell A B KE

Okay. Now let us look at the same problem from the perspective of the KE and PE of individual atoms. initial final

Okay. Now let us look at the same problem from the perspective of the KE and PE of individual atoms. initial final

Particle Model of E thermal E thermal is the energy associated with the random microscopic motions and vibrations of the particles.

Particle Model of E thermal E thermal is the energy associated with the random microscopic motions and vibrations of the particles. We increased E thermal by putting more energy into the system

Particle Model of E thermal E thermal is the energy associated with the random microscopic motions and vibrations of the particles. We increased E thermal by putting more energy into the system KE and PE keep changing into one another as the atoms vibrate, so we cannot make meaningful statements about instantaneous KE and PE

Particle Model of E thermal E thermal is the energy associated with the random microscopic motions and vibrations of the particles. We increased E thermal by putting more energy into the system KE and PE keep changing into one another as the atoms vibrate, so we cannot make meaningful statements about instantaneous KE and PE We can make statements about average KE and PE.

Particle Model of E thermal E thermal is the energy associated with the random microscopic motions and vibrations of the particles. We increased E thermal by putting more energy into the system KE and PE keep changing into one another as the atoms vibrate, so we cannot make meaningful statements about instantaneous KE and PE We can make statements about average KE and PE. Increasing E thermal increases BOTH KE average and PE average

Particle Model of E thermal and E bond The energy associated with the random motion of particles is split between PE oscillation and KE.

Mass on Spring Energy position As we increase E tot we increase PE ave and KE ave PE ave = KE ave = E tot /2 E tot PE KE

Particle Model of E thermal and E bond The energy associated with the random motion of particles is split between PE oscillation and KE.

Particle Model of E thermal and E bond The energy associated with the random motion of particles is split between PE oscillation and KE. For particles in liquids and solids, let’s not forget the part of PE hat correspond to E bond of the system. E bond of the system is determined by both the depth of the pair-wise potential well and the number of nearest-neighbors.

Particle Model of E thermal and E bond The energy associated with the random motion of particles is split between PE oscillation and KE. For particles in liquids and solids, let’s not forget the part of PE hat correspond to E bond of the system. E bond of the system is determined by both the depth of the pair-wise potential well and the number of nearest-neighbors. For solids and liquids, KE all atoms = (1/2)E thermal PE all atoms = PE bond + PE oscillation = E bond (PE bond )+ (1/2)E thermal (PE oscillation ) => KE all atoms + PE all atoms = E thermal + E bond

Particle Model of E thermal and E bond The energy associated with the random motion of particles is split between PE oscillation and KE. For particles in liquids and solids, let’s not forget the part of PE hat correspond to E bond of the system. E bond of the system is determined by both the depth of the pair-wise potential well and the number of nearest-neighbors. For solids and liquids, KE all atoms = (1/2)E thermal PE all atoms = PE bond + PE oscillation = E bond (PE bond )+ (1/2)E thermal (PE oscillation ) => KE all atoms + PE all atoms = E thermal + E bond In the gas phase, there are no springs, so there is no PE oscillation or PE bond

If the atoms do not move too far, the forces between them can be modeled as if there were springs between the atoms. Each particle in a solid or liquid oscillates in 3 dimensions about its equilibrium positions as determined by its single-particle potential. Intro to Equipartition of Energy

Another way of saying is, each particle has six “ways” to store the energy associated with its random thermal motion. We call this “way” for a system to have thermal energy as a “mode”. Intro to Equipartition of Energy

Closed Book Don’t forget to fill in your DL section number! !!THIS QUIZ IS TWO-SIDED!!