PHYS 6A Lecture Notes - Lecture 2: Pythagorean Theorem, Significant Figures, International System Of Units
Document Summary
Si units form one type of metric system: factors of 10 to span range of values (rather than factors of 12) Prefixes: giga g, mega m, kilo k, milli m, micro m, nano n, pico p: Unit conversion multiply by 1 : ex: convert 50 m to km 50 m x (1 km / 1000 m) = 0. 050 km. Multiplication and division (0"s aren"t significant figures. Just place keepers: rule: the result has same number of significant figures as the quantity having the least significant figures entering into calculation. Addition and subtraction: rule: the last significant figure is in the same column as last significant figure in the least accurate number. Scalars: quantity with magnitude but no direction: time, weight, distance, mass, temp , speed, volume. Vectors: magnitude and direction: velocity, displacement, force, note: magnitude of a vector is just a scalar, notation: small arrow over vector. Method 1: graphical: | a | = 5 km.
