Lecturer 1 Basics of Physics.pdf
- 1. Applied Physics Lecturer 1 ENGR. TEHSEEN HUSSAIN 1
- 2. Applied Physics, Credit Hours: (3+0) Catalog Description Measurement, Motion Along a Straight Line, Vectors, Motion in Two and Three Dimensions, Force and Motion, Kinetic Energy and Work, Potential Energy and Conservation of Energy, Center of Mass and Linear Momentum, Rotation, Torque and Angular Momentum, Equilibrium and Elasticity, Gravitation. Fluids, Oscillations, Waves, First Law of Thermodynamics, Entropy and the Second Law of Thermodynamics, Electric charge, Electric Fields, Gauss’ Law, Electric Potential, Capacitance, Current and Resistance, Circuits, Magnetic Fields, Magnetic Fields Due to Currents, Induction and Inductance, Electromagnetic Oscillations and Alternating Current, Maxwell’s Equations. Textbook: Halliday, Resnick and walker “Fundamentals of Physics” 10th Edition. 2
- 3. Course Learning Outcomes (CLO’s) Upon successful completion of this course, students will be able to: CLO 1. Define the basic terminologies and fundamental laws of applied physics relevant to the engineering sciences. CLO 2. Apply knowledge of basic physical laws to solve various problems of applied physics.
- 4. Program Learning Outcomes (PLO’s) This course is designed in conjunction with the following PLOs: PLO-1: Engineering Knowledge: An ability to apply knowledge of mathematics, science, engineering fundamentals and an engineering specialization to the solution of complex engineering problems.
- 5. Mapping of CLO’s to PLO’s Program Learning Outcome Course Learning Outcome Learning Domain PLO-1 CLO-1 Cognitive 1 PLO-1 CLO-2 Cognitive 3
- 6. Chapter 1. Measurement 1.WHAT IS PHYSICS? 2. MEASURING THINGS 3. THE INTERNATIONAL SYSTEM OF UNITS 4. LENGTH 5. TIME 6. MASS 7. CHANGING UNITS 8.CALCULATIONS WITH UNCERTAIN QUANTITIES 6
- 7. What Is Physics? Physics is the study of the basic components of the universe and their interactions. Theories of physics have to be verified by the experimental measurements. Science and engineering are based on measurements and comparisons. Need of rules about how things are measured and compared we need experiments to establish the units for those measurements and comparisons. Example: For example, physicists strive to develop clocks of extreme accuracy so that any time or time interval can be precisely determined and compared (GPS System) 7
- 8. Measurements A scientific measurement requires: The definition of the physical quantity The units. The value of a physical quantity is actually the product of a number and a unit . We measure each physical quantity in its own units, by comparison with a standard. The unit is a unique name we assign to measures of that quantity— for example, meter (m) for the quantity length. The standard corresponds to exactly 1.0 unit of the quantity. 8
- 9. Base and Derived Quantities Base standards must be both accessible and invariable. If we define the length standard as the distance between one’s nose and the index finger on an outstretched arm, we certainly have an accessible standard— but it will, of course, vary from person to person. The demand for precision in science and engineering pushes us to aim first for invariability. We then exert great effort to make duplicates of the base standards that are accessible to those who need them. The International System of Units 9
- 10. Scientific Notation To express the very large and very small quantities, we use scientific notation 10 4700000 0.0000065
- 11. Changing Units In chain-link conversion, we multiply the original measurement by one or more conversion factors. A conversion factor is defined as a ratio of units that is equal to 1. For example, because 1 mile and 1.61 kilometers are identical distances, we have: 11 • Convert 2Mints into Seconds
- 12. Basic Measurements in the Study of Motion Length: Our “How far?” question involves being able to measure the distance between two points. • Time: To answer the question, “How long did it take?” • Mass: Mass is a measure of “amount of stuff.” 12
- 13. Length Definition 1:The meter came to be defined as the distance between two fine lines engraved near the ends of a platinum–iridium bar, the standard meter bar, which was kept at the International Bureau of Weights and Measures near Paris. Definition 2: In 1960, a new standard for the meter, based on the wavelength of light, was adopted. Specifically, the standard for the meter was redefined to be 1 650 763.73 wavelengths of a particular orange-red light emitted by atoms of krypton-86 (a particular isotope, or type, of krypton) in a gas discharge tube that can be set up anywhere in the world. Definition 3: The meter is the length of the path travelled by light in a vacuum during a time interval of 1/299 792 458 of a second. 13
- 14. Time The quartz clock keeps better time than the best mechanical clocks. It contains a specially cut quartz crystal that vibrates at a particular frequency when voltage is applied. The vibrations can be sustained in an electrical circuit and will generate a signal of constant frequency that can be used to keep time. SI Definition: One second is the time taken by 9 192 631 770 oscillations of the light (of a specified wavelength) emitted by a cesium-133 atom or One second is the duration of 9.192631770 × 109 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium-133 atom. This definition is based on the operation of a caesium atomic clock. 14
- 15. Mass Mass: One kilogram is the mass of this thing (a platinum-iridium cylinder of height=diameter=39 mm) 15