Applied Physics Lecture: Fluids

Lesson Objectives - the students should be able to:

• Distinguish between density, weight density, and specific gravity and given an object's mass and volume, calculate the object's density, weight density, and specific gravity.
• Define pressure and calculate the pressure that an object of known weight exerts on a surface of known area and express the magnitude of the pressure in psi, lb/ft², N/m², or pascals (Pa).
• Calculate the pressure acting at a depth h below the surface of a liquid of density (ρ).
• Distinguish between absolute pressure and gauge pressure and solve problems involving each type of pressure.
• State Pascal's Principle and apply this principle to basic hydraulic systems.
• State Archimedes Principle and use this principle to solve problems related to buoyancy.
• Explain what is meant by streamline flow, the equation of continuity, and the flow rate. Apply these concepts to word problems to solve for the velocity of water at a particular point in a closed pipe.
• Use Bernoulli's equation and the concept of streamline flow to solve for the velocity of a fluid and/or the pressure exerted by a fluid at a particular point in a closed pipe.

Lecture on Fluids PPT

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• Applied Physics Course Outline

Summary of Chapter 10

• Phases of matter: solid, liquid, gas.
• Liquids and gases are called fluids.
• Density is mass per unit volume.
• Specific gravity is the ratio of the density of the material to that of water.
• Pressure is force per unit area.
• Pressure at a depth h is ρgh.
• External pressure applied to a confined fluid is transmitted throughout the fluid.
• Atmospheric pressure is measured with a barometer.
• Gauge pressure is the total pressure minus the atmospheric pressure.
• An object submerged partly or wholly in a fluid is buoyed up by a force equal to the weight of the fluid it displaces.
• Fluid flow can be laminar or turbulent.
• The product of the cross-sectional area and the speed is constant for horizontal flow.
• Where the velocity of a fluid is high, the pressure is low, and vice versa.
• Viscosity is an internal frictional force within fluids.
• Liquid surfaces hold together as if under tension.

Units of Chapter 10 - Keywords

• Density and Specific GravityDensity and Specific Gravity
• Density and Specific Gravity
• Pressure in Fluids
• Atmospheric Pressure and Gauge Pressure
• Pascal’s Principle
• Measurement of Pressure; Gauges and the Barometer
• Buoyancy and Archimedes’ Principle
• Fluids in Motion; Flow Rate and the Equation of Continuity
• Bernoulli’s Equation
• Applications of Bernoulli’s Principle: from Torricelli to Airplanes, Baseballs, and TIA
• Viscosity
• Flow in Tubes: Poiseuille’s Equation, Blood Flow
• Surface Tension and Capillarity
• Pumps, and the Heart

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Applied Physics Lecture: Electric Currents

Lesson Objectives - the students should be able to:

• Explain how a simple battery can produce an electrical current.
• Define current, ampere, emf, voltage, resistance, resistivity, and temperature coefficient of resistance.
• Write the symbols used for electromotive force, electric current, resistance, resistivity, temperature coefficient of resistance and power and state the unit associated with each quantity.
• Distinguish between a) conventional current and electron current and b) direct current and alternating current.
• Know the symbols used to represent a source of emf, resistor, voltmeter, and ammeter and how to interpret a simple circuit diagram.
• Given the length, cross sectional area, resistivity, and temperature coefficient of resistance, determine a wire's resistance at room temperature and some higher or lower temperature.
• Solve simple dc circuit problems using Ohm's law.
• Use the equations for electric power to determine the power and energy dissipated in a resistor and calculate the cost of this energy to the consumer.
• Distinguish between the rms and peak values for current and voltage and apply these concepts in solving problems involving a simple ac circuit.
• Compute Power in Household Circuits
• Understand the Microscopic View of Electric Current
• Learn the concept of Superconductivity
• Could understand the Electrical Conduction in the Human Nervous System

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• Applied Physics Course Outline

Summary of Chapter 18

• A battery is a source of constant potential difference.
• Electric current is the rate of flow of electric charge.
• Conventional current is in the direction that positive charge would flow.
• Resistance is the ratio of voltage to current:
  
  
• Ohmic materials have constant resistance, independent of voltage.
• Resistance is determined by shape and material:
  
  
• ρ is the resistivity.
• Power in an electric circuit:
  
  
• Direct current is constant
• Alternating current varies sinusoidally
  
  
• The average (rms) current and voltage:
  
  
• Relation between drift speed and current:
  
  

Units of Chapter 18 - Keywords

• The Electric Battery
• Electric Current
• Ohm’s Law: Resistance and Resistors
• Resistivity
• Electric Power
• Power in Household Circuits
• Alternating Current
• Microscopic View of Electric Current
• Superconductivity
• Electrical Conduction in the Human Nervous System
• Volta
• electrolyte

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Applied Physics Lecture: Electric Potential

Lesson Objectives - the students should be able to:

• Write from memory the definitions of electric potential, and electric potential difference.
• Distinguish between electric potential, electric potential energy, and electric potential difference.
• Draw the electric field pattern and equipotential line pattern which exist between charged objects.
• Determine the magnitude of the potential at a point a known distance from a point charge or an arrangement of point charges.
• State the relationship between electric potential and electric field and determine the potential difference between two points a fixed distance apart in a region where the electric field is uniform.
• Determine the kinetic energy in both joules and electron volts of a charged particle which is accelerated through a given potential difference.
• Explain what is meant by an electric dipole and determine the magnitude of the electric dipole moment between two point charges.
• Given the dimensions, distance between the plates, and the dielectric constant of the material between the plates, determine the magnitude of the capacitance of a parallel plate capacitor.
• Given the capacitance, the dielectric constant, and either the potential difference or the charge stored on the plates of a parallel plate capacitor, determine the energy and the energy density stored in the capacitor.
• Understand the functions and operations of Cathode Ray Tube: TV and Computer Monitors, Oscilloscope
• Know The Electrocardiogram (ECG or EKG)

Lecture on Electric Potential PPT

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• Applied Physics Course Outline

Summary of Chapter 17

• Electric potential energy:
  
  
• Electric potential difference: work done to move charge from one point to another
• Relationship between potential difference and field:
  
  
• Equipotential: line or surface along which potential is the same
• Electric potential of a point charge:
  
  
• Electric dipole potential:
  
  
• Capacitor: nontouching conductors carrying equal and opposite charge
• Capacitance:
  
  
• Capacitance of a parallel-plate capacitor:
  
  
• A dielectric is an insulator
• Dielectric constant gives ratio of total field to external field
• Energy density in electric field:
  
  

Units of Chapter 17 - Keywords

• Electric Potential Energy and Potential Difference
• Relation between Electric Potential and Electric Field
• Equipotential Lines
• The Electron Volt, a Unit of Energy
• Electric Potential Due to Point Charges
• Potential Due to Electric Dipole; Dipole Moment
• Capacitance
• Dielectrics
• Storage of Electric Energy
• Cathode Ray Tube: TV and Computer Monitors, Oscilloscope
• The Electrocardiogram (ECG or EKG)

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Chapter Quiz: Temperature and Kinetic Theory- MCQs

Begin and Good luck!

1. Which is the largest unit: one Celsius degree, one Kelvin degree, or one Fahrenheit degree?

• A) one Celsius degree
• B) one Kelvin degree
• C) one Fahrenheit degree
• D) both one Celsius degree and one Kelvin degree
• E) both one Fahrenheit degree and one Celsius degree

2. It turns out that – 40°C is the same temperature as – 40°F. Is there a temperature at which the Kelvin and Celsius scales agree?

• A) yes, at 0 °C
• B) yes, at -273 °C
• C) yes, at 0 K
• D) no

3. You may notice that if a mercury-in-glass thermometer is inserted into a hot liquid, the mercury column first drops, and then later starts to rise (as you expect). How do you explain this drop?

• A) the mercury contracts before the glass contracts
• B) the glass contracts before the mercury contracts
• C) the mercury contracts before the glass expands
• D) the glass expands before the mercury expands

4. Two drinking glasses are stuck, one inside the other. How would you get them unstuck?

• A) run hot water over them both
• B) put hot water in the inner one
• C) run hot water over the outer one
• D) run cold water over them both
• E) break the glasses

5. A steel tape measure is marked such that it gives accurate length measurements at room temperature. If the tape measure is used outside on a very hot day, how will its length measurements be affected?

• A) measured lengths will be too small
• B) measured lengths will still be accurate
• C) measured lengths will be too big

6. Metals such as brass expand when heated. The thin brass plate in the movie has a circular hole in its center. When the plate is heated, what will happen to the hole?

• A) gets larger
• B) gets smaller
• C) stays the same
• D) vanishes

7. A steel ring stands on edge with a rod of some material inside. As this system is heated, for which of the following rod materials will the rod eventually touch the top of the ring?

• A) aluminum
• B) steel
• C) glass
• D) aluminum and steel
• E) all three

8. You want to take apart a couple of aluminum parts held together by steel screws, but the screws are stuck. What should you do?

• A) heat the thing up
• B) cool the thing down
• C) blow the thing up

9. A grandfather clock uses a brass pendulum to keep perfect time at room temperature. If the air conditioning breaks down on a very hot summer day, how will the grandfather clock be affected?

• A) clock will run slower than usual
• B) clock will still keep perfect time
• C) clock will run faster than usual

10. Which has more molecules – a mole of nitrogen (N₂) gas or a mole of oxygen (O₂) gas?

• A) oxygen
• B) nitrogen
• C) both the same

11. Which weighs more – a mole of nitrogen (N₂) gas or a mole of oxygen (O₂) gas?

• A) oxygen
• B) nitrogen
• C) both the same

12. Two identical cylinders at the same temperature contain the same gas. If A contains three times as much gas as B, which cylinder has the higher pressure?

• A) cylinder A
• B) cylinder B
• C) both the same
• D) it depends on temp. T

13. Two identical cylinders at the same pressure contain the same gas. If A contains three times as much gas as B, which cylinder has the higher temperature?

• A) cylinder A
• B) cylinder B
• C) both the same
• D) it depends on temp. T

14. Two identical cylinders at the same temperature contain the same gas. If B has twice the volume and half the number of moles as A, how does the pressure in B compare with the pressure in A?

• A) P_B = 1/2 P_A
• B) P_B = 2 P_A
• C) P_B = 1/4 P_A
• D) P_B = 4 P_A
• E) P_B = P_A

15. A plastic soda bottle is empty and sits out in the sun, heating the air inside. Now you put the cap on tightly and put the bottle in the fridge. What happens to the bottle as it cools?

• A) it expands and may burst
• B) it does not change
• C) it contracts and the sides collapse inward
• D) it is too dark in the fridge to tell

16. What happens to the volume of a balloon if you put it in the freezer?

• A) it increases
• B) it does not change
• C) it decreases

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Chapter Quiz: Sound - MCQs

Begin and Good luck!

1. When a sound wave passes from air into water, what properties of the wave will change?

• A)      the frequency f                     
• B)     the wavelength λ
• C)      the speed of the wave                   
• D)      both f and λ
• E)      both v_wave and λ

2. We just determined that the wavelength of the sound wave will change when it passes from air into water.   How will the wavelength change?

• A)      wavelength will increase     
• B)      wavelength will not change                    
• C)      wavelength will decrease

3. Do sound waves travel faster in water or in ice?

• A)      water                                                
• B)      ice    
• C)      same speed in both            
• D)      sound can only travel in a gas

4. Do you expect an echo to return to you more quickly or less quickly on a hot day, as compared to a cold day?

• A)      more quickly on a hot day   
• B)      equal times on both days                                 
• C)      more quickly on a cold day

5. If you fill your lungs with helium and then try talking, you sound like Donald Duck.   What conclusion can you reach about the speed of sound in helium?

• A)      speed of sound is less in helium
• B)      speed of sound is the same in helium
• C)      speed of sound is greater in helium
• D)      this effect has nothing to do with the  speed in helium

6. You drop a rock into a well, and you hear the splash 1.5 s later.  If the depth of the well were doubled, how long after you drop the rock would you hear the splash in this case?

• A)      more than 3 s later                        
• B)      3 s later
• C)      between 1.5 s and 3 s later 
• D)      1.5 s later
• E)      less than 1.5 s later

7. You stand a certain distance away from a speaker and you hear a certain intensity of sound.  If you double your distance from the speaker, what happens to the sound intensity at your new position?

• A)      drops to 1/2 its original value 
• B)      drops to 1/4 its original value
• C)      drops to 1/8 its original value
• D)      drops to 1/16 its original value               
• E)      does not change at all

         

8. You hear a fire truck with a certain intensity, and you are about 1 mile away.   Another person hears the same fire truck with an intensity that is about 10 times less.   Roughly how far is the other person from the fire truck?

• A)      about the same distance               
• B)      about 3 miles
• C)      about 10 miles                      
• D)      about 30 miles
• E)      about 100 miles

9. When Mary talks, she creates an intensity level of 60 dB at your location.  Alice talks with the same volume, also giving 60 dB at your location.  If both Mary and Alice talk simultaneously from the same spot, what would be the new intensity level that you hear?

• A)      more than 120 dB                         
• B)     120 dB
• C)      between 60 dB and 120 dB
• D)      60 dB
• E)      less than 60 dB

10. A quiet radio has an intensity level of about 40 dB.   Busy street traffic has a level of about 70 dB.   How much greater is the intensity of the street traffic compared to the radio?

• A)      about the same                     
• B)      about 10 times
• C)      about 100 times                    
• D)      about 1000 times
• E)      about 10,000 times

11. Intensity level is given by β = 10 log(I/I₀) with I₀ = 10^-12 W/m².  The usual threshold of human hearing is defined as intensity level of β = 0 dB.  What does this actually mean in terms of sound intensity?

• A)      intensity is undefined at that level
• B)      intensity is 10⁰ W/m²
• C)      intensity is 0.0 W/m²
• D)      intensity is 10^-12 W/m²
• E)      intensity is 1.0 W/m²

12. You have a long pipe and a short pipe.   Which one has the higher frequency?

• A)      the long pipe                        
• B)      the short pipe
• C)      both have the same frequency    
• D)      depends on the speed of sound in the pipe

13. A wood whistle has a variable length.  You just heard the tone from the whistle at maximum length.  If the air column is made shorter by moving the end stop, what happens to the frequency?

• A)      frequency will increase        
• B)      frequency will not change
• C)      frequency will decrease

14. If you blow across the opening of a partially filled soda bottle, you hear a tone.  If you take a big sip of soda and then blow across the opening again, how will the frequency of the tone change?

• A)      frequency will increase        
• B)      frequency will not change
• C)      frequency will decrease

15. You blow into an open pipe and produce a tone.  What happens to the frequency of the tone if you close the end of the pipe and blow into it again?

• A)      depends on the speed of sound in the pipe
• B)      you hear the same frequency
• C)      you hear a higher frequency
• D)      you hear a lower frequency

16. When you tune a guitar string, what physical characteristic of the string are you actually changing?

• A)      the tension in the string
• B)      the mass per unit length of the string
• C)      the composition of the string
• D)      the overall length of the string
• E)      the inertia of the string

17. Speakers A and B emit sound waves of λ = 1 m, which interfere constructively at a donkey located far away (say, 200 m).   What happens to the sound intensity if speaker A steps back 2.5 m?

• A)      intensity increases               
• B)      intensity stays the same
• C)      intensity goes to zero
• D)      impossible to tell

18. The traces below show beats that occur when two different pairs of waves interfere.  For which case is the difference in frequency of the original waves greater?

• A)      pair 1                                               
• B)      pair 2
• C)      same for both pairs                       
• D)      impossible to tell by just looking

 19. Observers A, B, and C listen to a moving source of sound.  The location of the wave fronts of the moving source with respect to the observers is shown below.  Which of the following is true?

• A)      frequency is highest at A 
• B)      frequency is highest at B
• C)      frequency is highest at C
• D)      frequency is the same at all three points

20. You are heading toward an island in a speedboat and you see your friend standing on the shore, at the base of a cliff.  You sound the boat’s horn to alert your friend of your arrival.  If the horn has a rest frequency of f₀, what frequency does your friend hear?

• A)      lower than f₀                                                            
• B)      equal to f₀
• C)      higher than f₀

21. In the previous question, the horn had a rest frequency of f₀, and we found that your friend heard a higher frequency f₁ due to the Doppler shift.  The sound from the boat hits the cliff behind your friend and returns to you as an echo.  What is the frequency of the echo that you hear?

• A)      lower than f₀                                   
• B)      equal to f₀
• C)      higher than f₀ but lower than f₁       D)      equal to f₁
• E)      higher than f₁

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Applied Physics Lecture: Electric Charge and Electric Field

Lesson Objectives - the students should be able to:

• State from memory the magnitude and sign of the charge on an electron and proton and also state the mass of each particle.
• Apply Coulomb's law to determine the magnitude of the electrical force between point charges separated by a distance r and state whether the force will be one of attraction or repulsion.
• State from memory the law of conservation of charge.
• Distinguish between an insulator, a conductor, and a semi conductor and give examples of each.
• Explain the concept of electric field and determine the resultant electric field at a point some distance from two or more point charges.
• Determine the magnitude and direction of the electric force on a charged particle placed in an electric field.
• Sketch the electric field pattern in the region between charged objects.
• Use Gauss's law to determine the magnitude of the electric field in problems where static electric charge is distributed on a surface which is simple and symmetrical.
• Could understand Static Electricity; Electric Charge and Its Conservation
• Solving Problems Involving Coulomb’s Law and Vectors
• Learn Electric Forces in Molecular Biology: DNA Structure and Replication
• Understand Photocopy Machines and Computer Printers Use Electrostatics

Lecture on Electric Charge and Electric Field PPT

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• Applied Physics Course Outline

Summary of Chapter 16

• Two kinds of electric charge – positive and negative
• Charge is conserved
• Charge on electron:
  
  
• Conductors: electrons free to move
• Insulators: nonconductors
• Charge is quantized in units of e
• Objects can be charged by conduction or induction
• Coulomb’s law:
  
  
• Electric field is force per unit charge:
  
  
• Electric field of a point charge:
  
  
• Electric field can be represented by electric field lines
• Static electric field inside conductor is zero; surface field is perpendicular to surface
• Electric flux:
  
  
• Gauss’s law:
  
  

Units of Chapter 16 - Keywords

• Static Electricity; Electric Charge and Its Conservation
• Electric Charge in the Atom
• Insulators and Conductors
• Induced Charge; the Electroscope
• Coulomb’s Law
• Solving Problems Involving Coulomb’s Law and Vectors
• The Electric Field
• Field Lines
• Electric Fields and Conductors
• Gauss’s Law
• Electric Forces in Molecular Biology: DNA Structure and Replication
• Photocopy Machines and Computer Printers Use Electrostatics

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Applied Physics Lecture: The Laws of Thermodynamics

Lesson Objectives - the students should be able to:

• Explain what is meant by a physical system and distinguish between an open system and a closed system.
• State the first law of thermodynamics and use this law to solve problems.
• Distinguish between an isothermal process, isobaric process, isochoric process and adiabatic process and draw a PV diagram for each process.
• Calculate the work done by a gas from a PV diagram. Use the equations for an ideal gas and for the internal energy of a gas to calculate the change in internal energy of a gas and the heat added or removed during a thermodynamic process.
• Calculate the amount of heat which must be added or removed to change the temperature of a gas held in a closed container under conditions of constant volume or constant pressure.
• Write from memory and explain the meaning of three equivalent ways of stating the second law of thermodynamics.
• Use the first and second laws of thermodynamics to solve problems involving a Carnot engine.
• Distinguish between a reversible process and an irreversible process. Give examples of each type of process.
• Determine the change in entropy for a system in which the thermodynamic process is either reversible or irreversible.
• Distinguish between macrostate and microstate and solve problems involving the statistical interpretation of entropy.

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• Applied Physics Course Outline

Summary of Chapter 15

• First law of thermodynamics:
  
  
• Isothermal process: temperature is constant.
• Adiabatic process: no heat is exchanged.
• Work done by gas at constant pressure:
  
  
• Heat engine changes heat into useful work; needs temperature difference.
• Efficiency of a heat engine:
  
  
• Upper limit on efficiency:
  
  
• Refrigerators and air conditioners do work to extract heat from a cooler region and send it to a warmer region:
  
  
• A heat pump is similar:
  
  
• Second law of thermodynamics:
• heat flows spontaneously from a hot object to a cold one, but not the reverse
• a given amount of heat cannot be changed entirely to work
• natural processes tend to increase entropy.
• Change in entropy:
  
  
• Entropy is a measure of disorder.
• As time goes on, less and less energy is available to do useful work.

Units of Chapter 15 - Keywords

• The First Law of Thermodynamics
• Thermodynamic Processes and the First Law
• Human Metabolism and the First Law
• The Second Law of Thermodynamics – Introduction
• Heat Engines
• Refrigerators, Air Conditioners, and Heat Pumps
• Entropy and the Second Law of Thermodynamics
• Order to Disorder
• Unavailability of Energy; Heat Death
• Evolution and Growth; “Time’s Arrow”
• Statistical Interpretation of Entropy and the Second Law
• Thermal Pollution and Global Warming

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Applied Physics Lecture: Heat

Lesson Objectives - the students should be able to:

• Convert from joules to calories and kilocalories and vice versa.
• Distinguish between the concepts of temperature and heat.
• Explain what is meant by specific heat, latent heat of fusion, and latent heat of vaporization.
• Apply the law of conservation of energy to problems involving calorimetry.
• Distinguish the three ways that heat transfer occurs: conduction, convection, and radiation.
• Solve problems involving the rate of heat transfer by convection and radiation.

Lecture on Heat PPT

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• Applied Physics Course Outline

Summary of Chapter 14

• Internal energy U refers to the total energy of all molecules in an object. For an ideal monatomic gas,
  
  
• Heat is the transfer of energy from one object to another due to a temperature difference. Heat can be measured in joules or in calories.
• Specific heat of a substance is the energy required to change the temperature of a fixed amount of matter by 1° C.
• In an isolated system, heat gained by one part of the system must be lost by another.
• Calorimetry measures heat exchange quantitatively.
• Phase changes require energy even though the temperature does not change.
• Heat of fusion: amount of energy required to melt 1 kg of material.
• Heat of vaporization: amount of energy required to change 1 kg of material from liquid to vapor.
• Heat transfer takes place by conduction, convection, and radiation.
• In conduction, energy is transferred through the collisions of molecules in the substance.
• In convection, bulk quantities of the substance flow to areas of different temperature.
• Radiation is the transfer of energy by electromagnetic waves.

Units of Chapter 14 - Keywords

• Heat As Energy Transfer
• Internal Energy
• Specific Heat
• Calorimetry – Solving Problems
• Latent Heat
• Heat Transfer: Conduction
• Heat Transfer: Convection
• Heat Transfer: Radiation

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