PHY 102: Notes. FBDs and Buoyancy: How does one solve problems?

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1 PHY 102: Notes Chapter 9: Solids and Fluids (sections 3-7) 1. Density Difference between mass and weight density 2. Pressure:General Definition P = Read tip 9.1 pg 211 and summarize: 3. Pressure in a fluid P = Gauge pressure is different from Absolute pressure Pascal s Principle: Give an example Summarize: P absolute = P due to atm + P due to objects sitting on top + P due to fluid 4. Archimede s Principle B = FBDs and Buoyancy: How does one solve problems? 5. Fluids in Motion Bernoulli's Equation Can you Derive B from pressure differences for an object in a fluid? (Buoyant Hotel and Lab: Archemedes) Can you fill out the Unit Chart for pressure and density? Can you use FBDs to solve problems about objects floating (or sinking) in a fluid? (HW Problem #35 and Clay Boat) Can you recognize all of the factors contributing to absolute pressure? (U-Tubes and Pressure, Tutorial: Buoyancy) Can you distinguish between the different masses, volumes, and densities in all the concepts in this chapter? (A Review of Quantities: ch 9) Phys. 102: Topic Outline page 1 rev: Wtr. 2008

2 Chapter 10: Thermal Physics (sections 1-5 and chapter 12.1) 1. Temperature Scales and Conversion (application of graphs) 2. Thermometric Properties Size Thermal Expansion equations: Color Electical resistivity 3. Ideal Gasses Moles and the Periodic Table Ideal Gas Law General Form: Lots of constants (Rs and k)! Relationships between just two quantities. Kinetic Theory of Gasses Assumptions The main point is: 4. Laws of Thermodynamics 0th Law: 1st Law: U=Q+W PV Graphs (section 12.1) Can you fill out the Unit Chart for pressure and density? Can you use a graph to write an equation to convert from one temperature scale to another? Can you describe the changes in an object when its temperature changes? (Ch 10 Problem 11, 47) Can you describe the meaning of the area under a PV graph? (Chap 12 Problems 2, 5) Can you apply the Ideal Gas Law to describe the behavior of an ideal gas? (Ch 10 Problem 27, 31, 50 and Lab: Gas Law) Phys. 102: Notes page 2 rev: Wtr. 2008

3 Chapter 11: Energy in Thermal Processes (sections 1-4) 1. Calorimetry Heat Units Specific Heat Capacity Q = Keeping track of the Energy Keeping track of the Signs (How might Tip 11.3 apply?) Phase Changes Q = Solid/Liquid Latent heat of fusion Liquid/Gas Latent heat of vaporization Describe a material with a T vs. Qadded graph (Fig. 11.3) 2. Heat and Mechanical Energy Can you find the final temperature when several materials at different temperatures are combined? Do you understand how Heat can be added to the Work/Energy Theorem from PHY 101. Can you keep track of heat loss/gain and the corresponding signs in the equations for calorimetry and phase change problems? Can you reason through a process of checking whether the final result in a heat transfer problem will involve a phase change without knowing the final temperature? How many different things can you read from a T vs Qadded graph to describe a material? (Heating Al, T vs Q Graph) Can you solve problems involving thermal and mechanical energy? (Inverting Tube) Phys. 102: Notes page 3 rev: Wtr. 2008

4 Chapter 15: Electric Forces and Electric Fields (sections 1-5) 1. Electric Charge Properties Quantized Positive and Negative Repel (Like) Attract (Unlike) What happens with neutral objects? (charge separation) Units Charging by: Contact Induction 2. Force: Coulomb s Law F = Keeping track of ON and BY charges! Superposition: Vector Addition and Force Notation (review from PHY 101) 3. Electric Field Relationship to Force: Magnitude as E = Which charge is in the equation? Direction: Get from Field Maps or Force Direction Drawing Field Maps for Charge Distributions Point charge(s) Dipole Plates What can you read from an Electric Field Map? Can you draw a field map for a distribution of charges? Can you read a field map for information about forces and electric field magnitude and direction? (Chap 15 Problems 24, 27) Can you solve problems involving electric forces and electric fields for point charge distributions? (Chap 15 Problems 11, 37) Phys. 102: Notes page 4 rev: Wtr. 2008

5 Chapter 16: Electrical Energy and Capacitance (sections 1-5) 1. Electrical Potential Energy (PE e ) Work: Causes change in Energy Potential Energy around Point Charges: PE = Absolute Zero at r = infinity Superposition: Adding up for multiple charges F vs. x graph (Fig for example) Remember: It is a Scaler! (Quantity with sign) 2. Electric Potential (V) WATCH OUT! This is different from PE but the name is close! Potential around Point Charges: V = Remember: It is a Scaler! (Quantity with sign) 3. Electrical Potential Difference: ( V) Keeping track of signs! Conservation of Energy to figure out signs: K and PE Equation V = PE e and V when we don't have point charges. Equipotential Lines and Surfaces Map Which way will + charge move? Relationship between V and E 4. Compare/Contrast Electric and Gravitational Fields 5. Capacitance Can you draw equipotential lines for a distribution of charges or parallel plate capacitor? Can you read this diagram for information about forces, electric field V and PE? Can you describe the relationship (sign and magnitude) between work done by the magnetic field, V, and PE for regions with electric fields? (Tutorial: Electrical Potentail Difference) Can you solve problems involving electric potential energy and electric potential for point charge distributions? (Chap 16 Problems 11, 13, 17) Phys. 102: Notes page 5 rev: Wtr. 2008

6 Chapter 17: Current and Resistance (sections 1, 3-9) Current Resistance Ohm s Law Ohmic materials Resistivity Resistance depends on material, area, length Resistance depends on Temperature Superconductivity Power and Energy Use of Ammeter and Voltmeter in a circuit to measure: Resistance VoltageDifference Current Can you use V vs I data to classify a material as ohmic or not? (Lab: Thermometric Properties) Can you describe how the resistance of a wire depends on temperature, area, length and material? (Chap 17 Problems 17, 25) Can you compare the current through, voltage across and resistance of combinations of series and parallel resistors? (Tutorials: Circuits I and II, Chap 17 Problem 29) Can you properly use a digital multimeter to measure resistance, current and potential difference? (Lab: Ohm s Law) Phys. 102: Notes page 6 rev: Wtr. 2008

7 Chapter 18: DC Circuits (sections 1-4, 7) Source of EMF Internal resistance Batteries Solving simple DC resistor circuits Resistors in Series Resistors in Parallel Combinations of Series and Parallel Applications from chapters 17 and 18 House wiring Safety Medical Can you break a complicated resistor circuit down to its equivalent circuit? (Chap 18 Problem 41) Can you find the resistance, current through, voltage across, and the power dissipated for each resistor in a circuit? (Chap 18 Problem 41) Can you properly use a digital multimeter to measure resistance, current and potential difference? (Lab: Ohm s Law) Phys. 102: Notes page 7 rev: Wtr. 2008

8 Chapter 19: Magnetism (sections 1-4, 6-8) Magnetic Fields due to: Permanent magnets Current carrying wire Loops Solenoid Moving Charges in magnetic fields Force on Charged Particle in B Field Right hand Rule #1 Symbol conventions Point charge moves F = Charge moves due to current carrying wire F = Unit: Tesla = Applications Use RHR to explain: Loudspeaker Electromagnetic Pump Use Torque, Force on charge in B field and Magnetic Field around wire to explain how a Motor works. Spectrometer Can you draw magnetic field lines to describe the magnetic field due to magnets, wires (straight, loops or solenoids)? (Class Activity: Drawing Magnetic Field Lines, Tutorial: Magnetic Interactions) Can you describe (magnitude and direction) the force on moving charge in a magnetic field? (Chap 19 Problems 2-4, 30, 53, Tutorial: Magnetic Interactions) Can you explain (from basic principles) how a device such as a motor works? (Motor Worksheet, Chapter 19 Problem 23) Phys. 102: Notes page 8 rev: Wtr. 2008

9 Chapter 20: Induced Voltages and Inductance (sections 1-5) Induction Faraday's Law Flux Definition Unit: weber E N t Lenz's Law Qualitative: changing current and moving magnets Rotating loops Motional emf How many ways can the flux be changed? Applications Generators: AC and DC Transformers Can you find the flux through a loop at any angle with the field? (Chap 20 Problems) Can you describe the magnitude of the induced EMF from a variety of situations? (Chap 20 Problem 13) Can you describe the direction of the induced current from a variety of situations? (Chap 20 Problems 21-25, Tutorial: Lanz Law) Can you explain (from basic principles) how a device such as a generator works? (Chap 20 Problem 47) Phys. 102: Notes page 9 rev: Wtr. 2008