Presentation on theme: "The Language of Physics"— Presentation transcript:
1The Language of Physics Pearland ISD PhysicsMark Lesmeister
2Objectives Interpret data in tables and graphs. Distinguish common symbols used in equations.Recognize common equations and graphs.Convert units.Use dimensional analysis.
3Tools to make data easier to understand. TablesVery useful for displaying data precisely.The relationship between the quantities may not be clear.GraphsVisually display the relationship between two quantities.The precision of the data is limited by the scale of the graph.
4Tools to make data easier to understand. EquationsMathematically display the relationship between two quantities.Can be manipulated using algebra:
6Symbols used in physics equations S means “sum” or “total.”D means “difference” or “change in.”QuantitySymbolUnitsUnitAbbrev.Change in positionDx , DymetersmTime intervalDtsecondssMasskilogramskg
7Evaluating physics expressions Units are treated like other algebraic quantities in equations.Ex.: A car travels 20 m/s for 120 s. How far does the car travel?
8Dimensional analysisDimensional analysis- determining what units would result from a calculation. In order to be correct, a calculation must produce units of the proper dimension.Ex.
9Order of Magnitude Calculations Order of magnitude calculations are estimates made using orders of magnitude, that is, powers of 10.Ex.- How long is PHS, as an order of magnitude?
10Converting unitsTo convert units, multiply the quantity you wish to convert by fractions equalling one; that is, fractions with equivalent units in the numerator and denominator.For example, convert 20 m/s to km/hour.