FACULTY OF SCIENCE, AUTUMN 2007
PHYS 124 LEC A1 : Particles and Waves (Instructor: Marc de Montigny)
Walker, Physics, Chapter 1: Introduction to Physics
- Section 1.1: Physics and Laws of Nature Physics is a science, i.e. involves comparison of theory and experiment.
- Section 1.2: Units
- SI Units are
- meters (m) for length (p.3: in vacuum, light travels 299,792,458 m per sec)
- kilograms (kg) for mass
- seconds (s) for time (p.4: it takes 1 sec for radiation from cesium-133 to complete 91,192,631,770 cycles of oscillation)
- Ampère (A) for electric current
- Table 1-4 contains a list of prefixes
- Table 1-5 shows the dimensions of common physical quantities
- Section 1.3: Dimensional Analysis
- Read p. 5, Exercice 1-2
- P. 14, Problem 9
- Section 1.4: Significant Figures
- P.6: The number of significant figures after multiplication and division is equal to the number of significant figures in the least accurately known quantity
- P. 7: The number of decimal places after addition and subtraction is equal to the smallest number of decimal places in any of the individual terms
- read p.7 (Scientific Notation) and p.8 (Round-Off Error) to refresh your memory
- Section 1.5: Converting Units
- Example: my car requires 23.4 L to travel 170 mi. What is the gas consumption in L/100 km? [Answer: 8.61 L/100 km]
- Section 1.6: Orders of Magnitude For individual reading
- Section 1.7: Scalars and Vectors More about vectors in Chapter 3
- Scalar: determined by a single number (ex. temperature, pressure, volume)
- Vector: determined by a numerical value and a direction (ex. velocity, force, momentum). In n dimensions, a vector is defined by n numbers.
- Section 1.8: Problem Solving individual reading. We will have many opportunities to practice!