8/23/10
Post date: Aug 22, 2010 5:19:27 PM
Finish mystery tubes
revised models
additional data to support
what happens if new data disproves our theory?
a theory is the best explanation we can make with the data we have
laws are a different type of knowledge - a set of observations that ALWAYS occur in a given situation (Newton’s law of gravitation, Ohm’s law)
create a law related to tubes
THEORIES NEVER BECOME LAWS
Quiz
How do we know we have the right answer in science?
Describe the differences between hypothesis, theory, and law
Measurements
Are a form of observation
May provide evidence to help us formulate a theory
Accurate measurements help us make more accurate theories
Are based in time, distance, and mass
The SI system (the metric system)
Used everywhere except USA and Australia
Used in SCIENCE
Uses prefixes to make larger or smaller increments
Time (second) - related to frequency of radiation from Cs-133
Distance (meter) - distance traveled by light in a vaccuum in 1/ (299,792,458) seconds
Mass (kilogram) - mass of a platinum-iridium rod kept near Paris
Distances
How far between two points
Basic unit is the meter (m)
For small measurements, we use the centimeter (1/100th of a meter) or the millimeter (1/1000th of a meter)
For large measurements, we use the kilometer (1000 meters)
To measure distance, we can use meter sticks and rulers
Measurements and Graphing Lab
Due Tuesday, 8/23/10