PHYSICS 3A Lecture 1: Measurement _ Significant Figures
PHYSICS 3A verified notes
1/15View all
Document Summary
Physics 3a - lecture 1 - measurement / significant figures. Any measured quantity must be made with respect to a standard value, or unit. Velocity, acceleration, force, energy, power, momentum, density, which can be expressed in terms of basic quantities. Fundamental units, or combinations of units, must be the same on both sides of an equation. (it makes no sense to say 5 seconds is equal to 5 meters). If this is not true, then start on plan b since you know your equation is wrong. (speed) has units of (m/s) = m /s . Power = force*velocity (kg m/s )(m/s) = kg m /s . Vector quantities can have units, associated with the magnitude of the vector. Significant figures keep track of how precise a measured (or estimated) quantity is. Don"t count the zeros before the first non-zero digit. V = 2000 m/s is not equal to v=2000. 0 m/s, and neither are equal to v=2x10 m/s.
