learning log
Measurements and calculations
Chapter two was about measurements and calculations. The week started off with many notes including SI baises, SI prefixes, conversions, scientific notation, and significant figures. The SI baises include meters, seconds, kelvin, mole, and grams. These are used to measure length, time, tempature, the amount of a substance, and the mass of an object. The main SI prefixes are giga, mega, kilo, base unit, deci, centi, milli, micro, and nano. These prefixes help describe whatever is being measured. The conversions use these bases and prefixes to have an equal amount of length, time, ect. but explain it in a different way. An example of this is one meter equals one-thousand millimeters. It was then further explained that instead of writting all the zeros before or after the decimal when converting you can use scientific notation. This is used by moving the decimal a certain number of times to the left or right until one non-zero number is infront of it. Then, you take the number of decimal places you moved as trhe new number times ten to the exponent of the number of moves you made. However, you have to bear in mind that if your gets larger when carrying ie. the decimal moves to the left that the exponent will be a negitive number. The last information that was needed for measument and conversions was significant figures. To be a significant figure there are three rules. First, if the number is non-zero it is significant. Second, if it is a zero inbetween two significant numbers it is significant. Lastly, there are trailing zeros after the the decimal point it is significant. An intersting fact is that when you put numbers into scientific notation it shows all the significant figures. With pratice the general consepts were easy to understand. These pobles were done in class and at home. Lastly at the end of the week in preperation of the test a pratice test was taken coving the previous information.
Lab abstract
On Wednesday a lab was preformed to explain the information in pratice. Data was recorded for the following subjets of, volume, mass, area, and tempature. Then data was converted to fit the metric system. The data was then compared to the more accurate data of Mrs. V's calculations. Many groups we off from measuring incaurately while some were very close. From this lab it was learned how had it and inportant it is to have accurate data with the unknown and known variables.