Conversion Factors A
Table A.1 Length
mcmkmin.ftmi 1 meter 1 102 10−3 39.37 3.281 6.214 × 10−4 1 centimeter 10−2 110−5 0.3937 3.281 × 10−2 6.214 × 10−6 1 kilometer 103 105 13.937 × 104 3.281 × 103 0.621 4 1inch 2.540 × 10−2 2.540 2.540 × 10−5 18.333 × 10−2 1.578 × 10−5 1 foot 0.3048 30.48 3.048 × 10−4 12 1 1.894 × 10−4 1 mile 1 609 1.609 × 105 1.609 6.336 × 104 5280 1
Table A.2 Time
s min h day year 1 second 1 1.667 × 10−2 2.778 × 10−4 1.157 × 10−5 3.169 × 10−8 1 minute 60 1 1.667 × 10−2 6.994 × 10−4 1.901 × 10−6 1 hour 3600 60 1 4.167 × 10−2 1.141 × 10−4 1day 8.640 × 104 1440 24 1 2.738 × 10−5 1 year 3.156 × 107 5.259 × 105 8.766 × 103 365.2 1
Table A.3 Area
m2 cm2 ft2 in.2 1 square meter 1 104 10.76 1550 1 square centimeter 10−4 11.076 × 10−3 0.1550 1 square foot 9.290 × 10−2 929.0 1 144 1 square inch 6.452 × 10−4 6.452 6.944 × 10−3 1 Note 1 square kilometer = 247.108 acres
H. A. Radi and J. O. Rasmussen, Principles of Physics, 999 Undergraduate Lecture Notes in Physics, DOI: 10.1007/978-3-642-23026-4, © Springer-Verlag Berlin Heidelberg 2013 1000 A Conversion Factors
Table A.4 Volume
m3 cm3 Lft3 in.3 1 cubic meter 1 106 1000 35.51 6.102 × 104 1 cubic centimeter 10−6 11.000 × 10−3 3.531 × 10−5 6.102 × 10−2 1liter 1.000 × 10−3 1000 1 3.531 × 10−2 61.02 1 cubic foot 2.832 × 10−4 1 28.32 1 1728 1 cubic inch 1.639 × 10−4 16.39 1.639 × 10−2 5.787 × 10−4 1 Note 1 U.S. fluid gallon = 3.786L
Table A.5 Speed
m/s cm/s ft/s mi/h km/h 1 meter per second 1 102 3.281 2.237 3.6 1 centimeter per second 10−2 13.281 × 10−2 2.237 × 10−2 3.6 × 10−2 1 foot per second 0.3048 30.48 1 0.6818 1.097 1 mile per hour 0.4470 44.70 1.467 1 1.609 1 kilometer per hour 0.2778 27.78 0.9113 0.6214 1
Table A.6 Mass
kg g slug u 1 kilogram 1 103 6.852 × 10−2 6.024 × 1026 1gram 10−3 16.852 × 10−5 6.024 × 1023 1 slug 14.59 1.459 × 104 18.789 × 1027 1 atomic mass unit 1.660 × 10−27 1.660 × 10−24 1.137 × 10−28 1 Note 1 metric ton = 1000kg
Table A.7 Force
Nlb 1 newton 1 0.2248 1 pound 4.448 1
Table A.8 Work, energy, and heat
Jft.lb eV 1 joule 1 0.737 6 6.242 × 1018 1 foot-pound 1.356 1 8.464 × 1018 1electronvolt 1.602 × 10−19 1.182 × 10−19 1 1 calorie 4.186 3.087 2.613 × 1019 1 British thermal unit 1.055 × 103 7.779 × 102 6.585 × 1021 1 kilowatt hour 3.600 × 106 2.655 × 106 2.247 × 1025 A Conversion Factors 1001
Table A.8 Continued
cal Btu kWh 1 joule 0.2389 9.481 × 10−4 2.778 × 10−7 1 foot-pound 0.3239 1.285 × 10−3 3.766 × 10−7 1electronvolt 3.827 × 10−20 1.519 × 10−22 4.450 × 10−26 1 calorie 1 3.968 × 10−3 1.163 × 10−6 1 British thermal unit 2.520 × 102 12.930 × 10−4 1 kilowatt hour 8.601 × 105 3.413 × 102 1
Table A.9 Pressure
Pa atm cm Hg lb/in.2 lb/ft2 1 pascal 1 9.869 × 10−6 7.501 × 10−4 1.450 × 10−4 2.089 × 10−2 1 atmosphere 1.013 × 105 1 76 14.70 2.116 × 103 1 centimeter mercurya 1.333 × 103 1.316 × 10−2 1 0.194 3 27.85 1 pound per square inch 6.895 × 103 6.805 × 10−2 5.171 1 144 1 pound per square foot 47.88 4.725 × 10−4 3.591 × 10−2 6.944 × 10−3 1 aAt 0◦C and at a location where the free-fall acceleration has its “standard” value, 9.80665m/s2 Basic Rules and Formulas B
Scientific Notation
When numbers in powers of 10 are expressed in scientific notation are being multi- plied or divided, the following rules are very useful:
+ 10m × 10n = 10m n m (B.1) 10 − = 10m n 10n When powers of a given quantity x are multiplied or divided, the following rules hold:
xm × xn = xm+n xm (B.2) = xm−n xn
The Distance Between Two Points
In Fig. B.1, P(x1, y1) and Q(x2, y2) are two different points in the (x, y) plane. As we move from point P to point Q, the coordinates x and y change by amounts that we denote by x and y (read “delta x” and “delta y”). Thus:
The change in x = x = x − x 2 1 (B.3) The change in y = y = y2 − y1
One can calculate the distance between the two points P and Q from the theorem of Pythagoras in geometry such that:
H. A. Radi and J. O. Rasmussen, Principles of Physics, 1003 Undergraduate Lecture Notes in Physics, DOI: 10.1007/978-3-642-23026-4, © Springer-Verlag Berlin Heidelberg 2013 1004 B Basic Rules and Formulas 2 2 2 2 The distance PQ = ( x) + ( y) = (x2 − x1) + (y2 − y1) (B.4)
Fig. B.1 y-axis
Q(x2,y2)
y
P(x1,y1)
x-axis (0,0) o
Slope and the Equation of a Straight Line
The slope of a line (usually given the symbol m) on which two points P and Q lie, is defined as the ratio y/ x, see Fig. B.2. Thus: