PHYS114 Lecture 1: PHYS 114 Chapter 1
21 Sep 2018
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A testable framework of ideas that explain observations or experiments and has predictive value. Theory becomes a law when tested so many times. Can"t change and be universal and accurately measurable. Base units: can"t be derived from other units. Need at least 7 to explain the universe. Derived units: can be derived from the base units. Will be looking at the three base units: second (time), meter (length), kg (mass) We look for repeating phenomena to define a unit. The early attempts to measure time were not universal and not constant. Need to be able to keep the same time all around the world. Anything mechanical objects are not constant because friction, breaking down. Based one second by the rotation of the earth to be 1/86 400 of the time it takes the earth to complete one rotation on its axis. Wasn"t truly universal because of other planets will have different rotation speeds.
