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# [PHY103] Introduction to General Physics for Engineering Students 1/2013

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This talked was given on the first day of PHY103 class at KMUTT on August 8, 2013. It was the overview of the topics over in this physics.

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### [PHY103] Introduction to General Physics for Engineering Students 1/2013

1. 1. “Vectors. Adding and multiplying vectors. Systems of particles and Newton's 2nd Law. Linear momentum. Center of mass. Conservation of angular momentum. Systems with varying mass. Collisions in 1D and 2D. Rotation of rigid body. Rolling, torque, and angular momentum. Fluid mechanics. Simple harmonic oscillations. Wave propagation. Sound waves. Heat. Entropy.The 1st and 2nd laws of thermodynamics. Kinetic theory of gasses.” Course Description --- quoted from physics curriculum (2009) PHY 103 Physics for Engineering Students (3-0-6) ดร.วรวรงค์ รักเรืองเดช ดร.อัฐพล กลั่นบุศย์ ภาควิชาฟิสิกส์ คณะวิทยาศาสตร์ มจธ. วิชาฟิสิกส์พื้นฐานสำหรับนักศึกษาวิศวกรรมศาสตร์ (เครื่องกล) Teaching and Research Team + ‘Total of 200 Students’ ‘Small groups of 5’ 2 Instructors: •Worawarong R. •Uttapol K. 4 Facilitators: • Kachanon N. (LI) • Banyat L. (LI) • Marut P. (LI) • Tossaporn L. (Ph.D. student) Teaching and Research Team 1 Grader • Nantarat SCL 2109 Studio Lab: CB24XX learning space (ME?) outside the classroom space e-learning Physics Book High-School Physics Motion Types translation 2D projectile circular Simple Harmonic Oscillator (SHO) 1Dlinear 3D Rotation Oscillations Relevant Quantities position & displacement (~x) speed & velocity (~v) acceleration (~a) time (t) tools graphing calculus "rate of change" Laws Newton's Laws 1st law v = const, if F = 0 2nd law F = ma Force (F) Total Force equillibrium collisions Friction mass (m) acceleration (a) T = I*a Torque & Moment การบิด การดัด Moment of Inertia (I) angular acceleration 3rd law action = reaction choosing relevant force Gravitational Law of Newton F = Gm1m2/r^2 Body Rigid Bodies Fluids (Force) Field Energy Heat Electric and Magnetic Radiation and Nuclear Energy Types Fusion Fission E = mc^2 nuclear reaction applications power plants radioactive substances types properties sources environmental impacts Waves mechanicalv = lambda * f Sound sound pollution Phenomena beats standing waves doppler shock waves resonances Hearing sound quality pitch intensity / sound level sources properties parameters Electromagnetic Light geometrical reﬂection mirrors planar spherical refraction Snell's law index of refraction total internal reﬂection (TIR) apperant depth lens concave convex physical interference diffraction gratingscattering spectrum color seeing matter waves Heuygen principles Typespotential kinetic work rate of doing work = power Essentials Quantities SI Units Mathematics Calculus derivatives integrals Table and Graphing Vector Adding Multiplying Problem Analysis Free-Body Diagram Main ConceptPhysics = Quantitative Science Measurement accuracy uncertainty signiﬁcant ﬁgures Comparison Ideas Mass balance *** Electricity and magnetism Electrical & Magnetic Components Capacitor Inductors Resistance Battery Transformer Devices / Appliances Principles Maxwell's Equations Charges Static Moving Current Electromagnetic Waves Free space In materials Fields Electric Magnetic ***Quantum Mechanics Failure of classical physics Planck Hypothesis Duality of LightPhotoelectric effect Quantum Computer Atoms Lorentz Model"Spring-like" Bohr Atom Quantized energy spectrum Quantum Model Schrodinger Equation Wavefunctions Uncertainty Principle Probabilistics High-School Physics Motion Types translation 2D projectile circular Simple Harmonic Oscillator (SHO) 1Dlinear 3D Rotation Oscillations Relevant Quantities position & displacement (~x) speed & velocity (~v) acceleration (~a) time (t) tools graphing calculus "rate of change" Laws Newton's Laws 1st law v = const, if F = 0 2nd law F = ma Force (F) Total Force equillibrium collisions Friction mass (m) acceleration (a) T = I*a Torque & Moment การบิด การดัด Moment of Inertia (I) angular acceleration 3rd law action = reaction choosing relevant force Gravitational Law of Newton F = Gm1m2/r^2 Body Rigid Bodies Fluids (Force) Field Energy Heat Electric and Magnetic Radiation and Nuclear Energy Types Fusion Fission E = mc^2 nuclear reaction applications power plants radioactive substances types properties sources environmental impacts Waves mechanicalv = lambda * f Sound sound pollution Phenomena beats standing waves doppler shock waves resonances Hearing sound quality pitch intensity / sound level sources properties parameters Electromagnetic Light geometrical reﬂection mirrors planar spherical refraction Snell's law index of refraction total internal reﬂection (TIR) apperant depth lens concave convex physical interference diffraction gratingscattering spectrum color seeing matter waves Heuygen principles Typespotential kinetic work rate of doing work = power Essentials Quantities SI Units Mathematics Calculus derivatives integrals Table and Graphing Vector Adding Multiplying Problem Analysis Free-Body Diagram Main ConceptPhysics = Quantitative Science Measurement accuracy uncertainty signiﬁcant ﬁgures Comparison Ideas Mass balance *** Electricity and magnetism Electrical & Magnetic Components Capacitor Inductors Resistance Battery Transformer Devices / Appliances Principles Maxwell's Equations Charges Static Moving Current Electromagnetic Waves Free space In materials Fields Electric Magnetic ***Quantum Mechanics Failure of classical physics Planck Hypothesis Duality of LightPhotoelectric effect Quantum Computer Atoms Lorentz Model"Spring-like" Bohr Atom Quantized energy spectrum Quantum Model Schrodinger Equation Wavefunctions Uncertainty Principle Probabilistics
2. 2. PHY: 103 Topics Mechanics Newton's laws Motion Types of motions Linear motion Periodic motion Simple Harmonic Circular Elliptical Oscillations Mapping mechanics with waves Mechanical Waves longtitudinal sound transverse string Angular motion Description space & time position, velocity, acceleration As a method of nature laws for making prediction Force linear angular Body Rigid System of particles Fluid Flow Lamina Turbulance Conservation Laws Momentum Angular LinearEnergy Essential toolsSystem of units Free body diagram Physics and quantitative science Measurement Comparison Scaling Laws Vectors adding multiplying Mathematics Table and graphs Calculus Heat & Thermodynamics Laws of thermodynamics 0th law thermal equillibrium 1st law Conservation of Energy 2nd law Set Nature's Direction Basic Quantities Energy Heat Transfer Conduction Convection Radiation Internal Energy System Work Temperature Scales Speciﬁc Heat Atomic Levels Kinetic theory of gases Gas laws Statistics Bulk Properties *** Electricity and magnetism ***Quantum Mechanics Waves Types Mechanical Waves Electromagnetic Waves Light Matter Waves Parameters Frequency / Amplitude / Phase / Polarization / Propagation direction สอบกลางภาค สอบปลายภาค สอบปลายภาค wk 1 wk 2 wk 3 wk 4 wk 5 wk 6 wk 7 wk 8 wk 9 wk 9 wk 10 wk 11 wk 12 wk 13 wk 13 wk 14 wk 15 wk 16 wk 17 wk 18 Course Introduction & Tracker Program Gaussian cannon (conservation laws) Paper bridge (analysis of structure) Loaded Hoop (Newton’s Laws) Ball Levitation (Fluid dynamics) Spinning top (Rotational Inertia) A simple pendulum? (Resonance condition) Review physics of musics (vibrations & sound) project consultation project performance Thermal comfort (thermodynamics I) water rise expt. (kinetic theory of gas) gasoline vs. diesel engines (thermo. II) Review รศ.ดร.พงษ์พันธุ์ ผศ.ดร.ชวิน ผศ.ดร.ยศพงษ์ อ.สุทธิพงษ์ / คชานนท์ คณาจารย์วิศวะเครื่องกล คณาจารย์วิศวะเครื่องกล (Tentative) Schedule of PHY103 in 1/56
3. 3. High-School Physics Motion Types translation 2D projectile circular Simple Harmonic Oscillator (SHO) 1Dlinear 3D Rotation Oscillations Relevant Quantities position & displacement (~x) speed & velocity (~v) acceleration (~a) time (t) tools graphing calculus "rate of change" Laws Newton's Laws 1st law v = const, if F = 0 2nd law F = ma Force (F) Total Force equillibrium collisions Friction mass (m) acceleration (a) T = I*a Torque & Moment การบิด การดัด Moment of Inertia (I) angular acceleration 3rd law action = reaction choosing relevant force Gravitational Law of Newton F = Gm1m2/r^2 Body Rigid Bodies Fluids (Force) Field Energy Heat Electric and Magnetic Radiation and Nuclear Energy Types Fusion Fission E = mc^2 nuclear reaction applications power plants radioactive substances types properties sources environmental impacts Waves mechanicalv = lambda * f Sound sound pollution Phenomena beats standing waves doppler shock waves resonances Hearing sound quality pitch intensity / sound level sources properties parameters Electromagnetic Light geometrical reﬂection mirrors planar spherical refraction Snell's law index of refraction total internal reﬂection (TIR) apperant depth lens concave convex physical interference diffraction gratingscattering spectrum color seeing matter waves Heuygen principles Typespotential kinetic work rate of doing work = power Essentials Quantities SI Units Mathematics Calculus derivatives integrals Table and Graphing Vector Adding Multiplying Problem Analysis Free-Body Diagram Main ConceptPhysics = Quantitative Science Measurement accuracy uncertainty signiﬁcant ﬁgures Comparison Ideas Mass balance *** Electricity and magnetism Electrical & Magnetic Components Capacitor Inductors Resistance Battery Transformer Devices / Appliances Principles Maxwell's Equations Charges Static Moving Current Electromagnetic Waves Free space In materials Fields Electric Magnetic ***Quantum Mechanics Failure of classical physics Planck Hypothesis Duality of LightPhotoelectric effect Quantum Computer Atoms Lorentz Model"Spring-like" Bohr Atom Quantized energy spectrum Quantum Model Schrodinger Equation Wavefunctions Uncertainty Principle Probabilistics Wk 1 (3hr): The core of “physics” ... the quantitative science: measurement and comparison / dimension analysis Physics is a quantitative science. Measurement and comparison are the keys. Quantity and units are essential for measurement and making comparison Key Concepts Dimension analysis and modeling ทบทวนความรูเดิม (เนื้อหา ม.ปลาย) 2 hr Going over course syllabus Good practice to solve a physics problem Key Success • ชี้แจงรายละเอียดของรายวิชา • สรางความตระหนักเกี่ยวกับศาสตร การวัดและการเปรียบเทียบ (measurement and comparison) • ทบทวนกรอบความรูเดิม (ม.ปลาย) • เลาเรื่อง dimension analysis F = ma represents an equation of motion, which is the cause of change of motion. Wk 2 (3hr): The “Cannon” ... vectors and motions via the Newton’s laws Key Concepts Free-body diagram is a drawing representing external forces acting on the object of interest. (dealing with F) “Monkey gun” acceleration of a ball free fall F = ma from kx ‘projectile’ motion Key Success Displacement, velocity, and acceleration represent ing “motion” are connected based on calculus (dealing with a) Vectors are useful for keeping tracks of magnitude and direction of a physical quantity ใชเครื่องยิงลูกเหล็กแบบโปรเจคไตลเปนตัวเชื่อมโยง • กฎของนิวตัน (ขอสอง) • เวกเตอรผานการรวมแรง และการเคลื่อนที่ (x/v/a) • การสรางโมเดลผานการวาด free-body diagram และทำการทดสอบพื้นความรูของนักศึกษา (1 hr pre-test) period of 1 hr: (16/8/56) pre-test เนื้อหา ม.ปลาย
4. 4. Wk 3 (3hr): Analysis of Structure ... the equilibrium of forces and moments Key Concepts Equilibrium of rigid body Condition for zero force and zero moment of forces. activity: invent yourself? Examples/techniques used are analysis of trusses & method of joints 1st and 3rd laws of Newton Key Success Conservation laws deal with constant of motion (energy / momentum / angular momentum) Wk 4 (3hr):The Gaussian Cannon ....the Conservation Laws: Energy and Linear Momentum. Key Concepts Conservation of momentum is valid when F = 0. It’s useful for describing collisions Types of collisions: elastic vs inelastic collisions. In both cases momentum and energy are always conserved Conservation of energy is always true. Energy cannot be destroyed or created. It only change forms. “Gaussian Cannon” F = ma can be describe as a rate of change of momentum (i.e. impulse) • ทบทวน condition of equilibrium and Newton’s laws of motion • ทำความเขาใจเกี่ยวกับการเคลื่อนที่ของลูกเหล็กที่ สัมพันธการเปลี่ยนรูปพลังงานของปนพลังแม เหล็ก... the Gaussian cannon • conservation laws: energy and linear momentum
5. 5. understand the basic principle of a gyroscope Wk 5 (3hr): Spinning “Top:” .... rotational motion via a gyroscope Conservation of angular momentum allows us to keep tracks of orientation (e.g. gyroscope) Key Concepts Parallel axis theorem is useful for ﬁnding moment of inertial at the pivot displaced from C.O.M. Moment of inertia is analogy to mass. It tells the property of the object and can be calculated by I = Integrate(r^2dm) Activities “Gyroscope” Goal: get a longest precision time on a spinning top: Design www.bgfl.org similarities and differences between linear and angular motions. Torque = (Moment of Inertia)*(angular acceleration) Parameters to adjust/explore: •moment of inertia of the disk (mass or length) •acceleration (torque and angle and time) •symmetry for stable rotation Work and Rotational Kinetic Energy • เชื่อมโยงความคลายคลึงระหวาง linear motion และ rotational motion • เขาใจเรื่อง torque, moment of inertia and angular acceleration • เขาใจการออกแบบการสราง spinning top ให หมุนไดเวลานานที่สุด The\$Kine(c\$Energy\$of\$Rolling\$ must\$take\$into\$account\$both\$rota(on\$and\$transla(on\$ 1 2 Icom 2 1 2 Mv2 com+ = (K.E.)rolling rota%onal(kine(c\$energy\$ due\$to\$rota(ons\$about\$ its\$center\$of\$mass\$ transla%onal(kine(c\$energy\$ due\$to\$transla(on\$of\$its\$ center\$of\$mass\$ Kine(c\$Energy\$(K.E.)\$ of\$a\$rolling\$object\$ Wk 6 (3hr): Hydraulic Lever and Ball’s Levitation. ... ﬂuid mechanics Design of hydraulic lever Pressure is vary with height and depth Pascal principle Key Concepts Buoyancy density How lift and drag created in imaginary stream(pipe)line basic parameters: density, pressure, air velocity / proﬁle. Key Success Bernoulli’s equation + equation of continuity. Laminar vs.Turbulence and signiﬁcance of Reynold number. Pascal’s'Principle'and'the'Hydraulic'Lever' Considering'the'work'done'by'the'output'piston,' W = Fodo = Fi Ao Ai ⇥ di Ai Ao ⇥ = Fidi Work'done'by'the'output'piston' in'li=ing'the'load'placed'on'it' Work'done'on'the'input' piston'by'the'applied'force' Hydraulic*Lever* Pascal’s*Principle:'A'change'in'the'pressure'applied'to'an'enclosed'incompressible'ﬂuid'is' transmiCed'undiminished'to'every'porDon'of'the'ﬂuid'and'to'the'walls'of'its'container.”' PhET Simulator |Fb| = mf g Buoyancy / lift / drag Av1 = Av2 This%rela*onship%also%apply%to%any%so0called%tube%of%ﬂow.%% Any%imaginary% ﬂow%whose% boundary%consists% of%streamlines.% Volume%ﬂow%rate% Mass%ﬂow%rate% RV = Av = const. Rm = RV = const. Equa*on%of% Con*nuity% Bernoulli’s+Equa/on+A+principle+of+ﬂuid+ﬂow+based+on+ conserva/on+of+energy+ p + 1 2 v2 + gy = constant • (คาบ 2 ชม.) โจทยใหเลน หามุมเอียงที่มากที่สุดที่ทำใหลูก ปงปองลอยไดดวยเครื่องเปาผม • (คาบ 1 ชม.) ใชไฮดรอลิกสที่สามารถเห็นไดในอุตสาหกรรม (air / oil) อนุเคราะหจากเครื่องกล? Density( (uniform)density)) = M V = lim V 0 m V = dm dV = m V For) a) small) volume) ∆V),)measuring)a)mass) ∆m,)the)density)is\$ For)a)inﬁnitesimal)volume)dV)with)a)mass) of)dm,)we)deﬁne)a)density) In)a)case)that)a)material) is) much) larger) than) atomic)dimensions,))
6. 6. Wk 7: Review of mechanics Physics is a quantitative science. Measurement and comparison are the keys. Quantity and units are essential for measurement and making comparison Dimension analysis and modeling Good practice to solve a physics problem Key Success F = ma represents an equation of motion, which is the cause of change of motion. Free-body diagram is a drawing representing external forces acting on the object of interest. (dealing with F) Displacement, velocity, and acceleration represent ing “motion” are connected based on calculus (dealing with a) Vectors are useful for keeping tracks of magnitude and direction of a physical quantity Wk 8: Midterm examination Equilibrium of rigid body Condition for zero force and zero moment of forces. Examples/techniques used are analysis of trusses & method of joints 1st and 3rd laws of Newton Conservation laws deal with constant of motion (energy / momentum / angular momentum) Conservation of momentum is valid when F = 0. It’s useful for describing collisions Types of collisions: elastic vs inelastic collisions. In both cases momentum and energy are always conserved Conservation of energy is always true. Energy cannot be destroyed or created. It only change forms. F = ma can be describe as a rate of change of momentum (i.e. impulse) Design of hydraulic lever Pressure is vary with height and depth Pascal principle How lift and drag created in imaginary stream(pipe)line basic parameters: density, pressure, air velocity / proﬁle. Bernoulli’s equation + equation of continuity. Laminar vs.Turbulence and signiﬁcance of Reynold number. Buoyancy / lift / drag wk 1 wk 2 wk 3 wk 4 wk 5 ทบทวนความเชื่อมโยงตั้งแตสัปดาหที่ 1 ถึง 5 และเตรียมความพรอมสำหรับการสอบกลางภาค คำนวณ 50% + ความเขาใจ 50% understand the basic principle of a gyroscope Conservation of angular momentum allows us to keep tracks of orientation (e.g. gyroscope) Parallel axis theorem is useful for ﬁnding moment of inertial at the pivot displaced from C.O.M. Moment of inertia is analogy to mass. It tells the property of the object and can be calculated by I = Integrate(r^2dm) similarities and differences between linear and angular motions. Torque = (Moment of Inertia)*(angular acceleration) wk 6 Applets Wk 9 (3hr):What is “Resonance”? ...Different types of Harmonic Motion (linear and angular dynamics) Key Concepts The key of “RESONANCE” phenomena: the matching of natural frequency and driving frequency. Resonance Pendulum understanding the way to write “differential equations” for simple harmonic motion, damped harmonic motion, and forced harmonic motion. the understanding of “natural frequency” with an example of (simple?) pendulum Understanding the limit of a simple pendulum, i.e. if (1) angle is small and (2) string is massless. Physical pendulum is useful for predicting the motion of a real pendulum Activities parameters: (1) mass of string (2) angle of pendulum (3) mass of the (4) ความยืดหยุ่นของ pendulum (5) .... “Explore the limit of the Simple Pendulum” Masses & Springs Forced Harmonic MotionDamped Harmonic Motion Important Oscillatory Motion Amplitude 8 1 ωm b = 12 2bb = 13 4bb = 0 0.5 1.0 1.5 2.0 ω ω "" ( )δtωsin G F )t(x m −""= (small&damping)& x = Fm G sin !!! t "!( ) ! G = m2 ""# 2 \$#2 ( ) 2 + b2 ""# 2 ! " # \$ % & '' = − G bω δ 1 cos Simple Harmonic Motion d2 x dt2 + k m x = 0 d2 x dt2 + b m dx dt + k m x = 0 d2 x dt2 + b m dx dt + k m x = Fm m cos 00 t x(t) = xme bt/2m cos(⇥⇥ t + ) = k m b2 4m2 Etotal = 1 2 kA2 1 2 kx2 me bt/m Key Success RESONANCE • เขาใจวิธีการเขียน diff. eq. ของ Harmonic motion รูปแบบตางๆ เริ่มดวย ระบบสปริง-มวล • เปรียบเทียบระบบ simple pendulum และ physical pendulum • เขาใจ simple harmonic motion, damped harmonic motion, and forced harmonic motion. • ทดลอง “simple pendulum” และเขาใจ the approximation behind และขอบเขตของระบบ “simple pendulum” เพื่อเขาใจ natural frequency. m มุม P!h!!!"! c!î! Ph!" îc # \$!!"#\$\$% Ph!" îc # \$!!"#\$\$%
7. 7. commons.wikimedia.org Frequency)of)sound)produced)by)membrane)instruments) + - + + +- - + +- -+ + + + + - - - - - f1 f2 = 1.59f1 f3 = 2.13f1 f4 = 2.30f1 f5 = 2.65f1 f6 = 2.92f1 Modes)of)drum)(standing)waves)) Node)line) +)and)=)stand)for)membrane)displacement)(concave)up)or)down)) Wk 10 (3hr): The Sound of Musics ..... mechanical waves (string and musics) Wave on a string Sound Wave Interference Fourier Making Waves (optional) Important parameters of musical instruments are sound quality, which depends on human perception and frequency mixing of the sound Key Concepts PhETsimulator:Applets types of waves: mechanical vs. electromagnetic, longitudinal vs transverse. Waves property: Superposition principles leading to simple calculation of interference and standing waves. Standing waves are description of ﬁxed positions. Wk 11 (3hr): Musical Instrument project: Do-it-yourself (DIY) Wk 12 (3hr): Musics performance.The presentation of students’ instrument project. ปรึกษาหารือ ซักซอม การแสดงกับดนตรีดวยเครื่องดนตรีที่แตละกลุมสรางขึ้นมา การแสดงดนตรีของนักศึกษา Guest speakers.. นักดนตรี / อ.สุทธิพงษ (GEN241 ความงดงามแหงชีวิต)? Revisit the “resonance” • แยกความแตกตางระหวาง sound intensity, sound level, sound quality, ear response. • แยกแยะความแตกตางระหวางเครื่องดนตรี ประเภทตางๆ เชน oscillating strings, membranes, wooden block, air column (close vs open ends)
8. 8. Wk 13-14 (6 hr): Thermal Comfort (heat + energy + kinetic theory of gas + laws of thermodynamics) Heat transfer mechanism Key Concepts Gas Properties PV-Diagram: state / process / work the heat and energy concepts Thermal Comfort (Y.A. Cengel, Heat and Mass Transfer:A Practical Approach, 3rd Ed., 2006, pp. 40-45) Heat and other forms of energy 1st law of thermodynamics - speciﬁc heat of gases, liquids and solids - PV=nRT - energy transfer - ∆E = Ein - Eout - rate forms: d/dt - ∆U = ∆Q + W - Heat balances Heat transfer mechanism - conduction: - dQ/dt = -kA*dT/dx - atomic motion in gas liquid and solid - thermal expansion - convection - dQ/dt = hAs(Ts-Tœ) - radiation - dQ/dt = c(Ts 4-Tsur 4) Heat loss from a person Introduction to engine mechanism (reading assignment, going to second laws of thermodynamics) - “state” vs “process” - Work is area under the curve - Examples of different types of processes (adiabatic, isotherm, isobaric) (optional:iftime’sallowed) Thermal expansion keywords:ASHRAE 55-2010 in-class activities (wk 2) water rise the 0th and 1st laws of thermodynamics state of matters and the phase diagram the PV digram introduction to the heat engine plotting the PV diagram of the ideal gas law. conduction / convection / radiation Wk 15 (3hr): KMUTT Ethanol Bus .... the implication of 2nd Law of Thermodynamics 1. Relevant parameters: -Internal Energy -Enthalpy -Entropy Key Concepts 2. Heat Engine •Concept of a heat engine •Mapping onto a PV Diagram •Calculate engine efﬁciency •Diesel vs gasoline engines Activities Equipment: (1) a clip video of Aj.Yossapong “How efﬁcient is an ethanol bus” Goal: compare the efﬁcient of ethanol engine used in a bus. gasoline diesel CERL: อ.ยศพงษ?