PHY 121 Tables and Formulas You may refer to this handout on quizzes and exams. Do not add additional information. e Sec. 1: ________________________________________________________________________ Sec. 2: Projectiles: No new formulas. ________________________________________________________________________ Sec. 3: Weight: W = mg -2- _______________________________________________________________________________ Sec. 4: _______________________________________________________________________________ Sec. 5: _______________________________________________________________________________ Sec. 6: ________________________________________________________________________________ Sec. 7: Newton's 3rd law: If A exerts a force on B, then B exerts an equal and opposite force on A. Momentum: p mv -3________________________________________________________________________________ Sec. 8: Moments of inertia: Particle of mass m, following orbit of radius r: I = mr2 Rigid bodies, total mass = M, outside radius = R: Hoop or tube, rotating about center: I = MR2 Solid cylinder or disk, rotating about center: I = (½)MR2 Solid sphere, rotating about center: I = (2/5)MR2 Thin spherical shell, rotating about center: I = (2/3)MR2 Thin rod, length L, rotating about center: I = (1/12)ML2 Thin rod, length L, rotating about one end: I = (1/3)ML2 ________________________________________________________________________________ Sec. 9: _______________________________________________________________________________________________________________________ Sec. 10: ________________________________________________________________________________ Sec. 11: Pascal's Principle: P increase at one point in an enclosed fluid = P increase at any other point. Archimedes' Principle: Buoyant force = weight of displaced fluid = (ρV)g -4- Ideal gas law: PV = nRT P & T: Absolute pressure and temperature, V = volume, n = number of moles, R = 8.314 J/mole.K Sec. 12: Heat gained from a change of temperature: Q = m c ΔT c = specific heat Heat gained from a change of state: Q = mLf or Q = mLv L = heat of fusion or vaporization _ In an insulated container, ∑Q = 0 ________________________________________________________________________________ Sec. 13: First law of thermodynamics: Q = ΔEint + W Q = heat added, ΔEint = internal energy gained, Isobaric process = no pressure change, Isothermal = No temperature change, 2nd law: Entropy won't spontaneously decrease. (Or, Heat won't spontaneously go cold to hot.) Work done in a cycle = Area enclosed on P-V diagram. e W QIN = W + QOUT emax 1 TOUT QIN TIN Efficiency: Efficiency of Carnot Cycle: ________________________________________________________________________________ _______________________________________________________________________________ -5- 2 Quadratic Formula: If ax + bx + c = 0 then x b b2 2a 4ac Some fundamental constants: Speed of light: c = 2.998 x 108 m/s Electron rest mass: me= 9.110 x 10-31 kg = (.5110 MeV)/c2 Proton rest mass: mp = 1.673 x 10-27 kg = (938.3 MeV)/c2 Neutron rest mass: mn = 1.675 x 10-27 kg = (939.6 MeV)/c2 Universal gas constant: R = 8.314 J/mole K Avogadro's Number: N0 = 6.022 x 1023 molecules/mole Some Physical Properties: Density of air at 20 C and 1 atmosphere 1.29 kg/m3 Density of water at 20 C 1000 kg/m3 (=1.0 gram/cm3) Mass of earth 5.99 x 1024 kg Radius of earth 6.37 x 106 m Standard atmospheric pressure 1.013 x 105 Pa Approximate Coefficients of Friction: S k wood on wood 0.5 0.3 steel on steel 0.74 0.57 teflon on teflon 0.04 0.04 S k rubber on dry concrete 1.0 0.8 rubber on wet concrete 0.7 0.5 metal on ice 0.03 0.01 -6- Expansion Coefficients (near room temperature): °C-1) 24 x 10-6 20 x 10-6 17 x 10-6 9 x 10-6 3.2 x 10-6 29 x 10-6 12 x 10-6 12 x 10-6 150 x 10-6 Aluminum Brass & bronze Copper Glass (ordinary) Glass (pyrex) Lead Steel & iron Concrete Vinyl siding °C-1) Ethyl alcohol 7.5 x 10-4 Benzene 1.24 x 10-4 Acetone 1.5 x 10-4 Glycerin 4.85 x 10-4 Mercury 1.82 x 10-4 Gasoline 9.6 x 10-4 Specific heat, c (at 25 C): Substance cal/g C Aluminum 0.217 Concrete 0.2 Copper 0.093 Gold 0.0308 Ice(-25-0 C) 0.48 Iron & Steel 0.112 Lead 0.0305 J/kg C 908 840 390 129 2010 469 128 CP CV (J/mol K) (J/mol K) He Ar Ne Kr 20.8 20.8 20.8 20.8 12.5 12.5 12.7 12.3 Substance cal/g C Silver 0.056 Tin 0.054 Zinc 0.092 J/kg C 234 226 385 Ethyl alcohol 0.58 Mercury 0.033 Water 1.00 Steam (1atm) 0.47 2430 140 4186 1970 CP CV (J/mol K) (J/mol K) 1.67 1.67 1.64 1.69 H2 N2 O2 CO 28.7 29.1 29.2 29.2 20.4 20.8 20.9 20.9 CP CV (J/mol K) (J/mol K) 1.41 1.40 1.40 1.40 CO2 SO2 H2O CH4 36.9 40.4 35.4 35.5 Heat of Fusion of water = 79.6 cal/g = 3.34 x 105 J/kg Heat of Vaporization of water = 539 cal/g = 2.26 x 106 J/kg 28.5 31.4 27.0 27.1 1.30 1.29 1.30 1.31 -7Units: Fundamental Units: Standard SI Unit: Conversion Factors: LENGTH meter = m 1 m = 3.28 ft, 1 mile = 1609 m = 5280 ft, 1 inch = 2.54 cm TIME second = s 1 hour = 3600 s, 1 day = 86,400 s, 1 year = 3.16 x 107 s MASS kilogram = kg TEMPERATURE kelvin = k 1kg = .0685 slug, weighs 2.21 lb in standard gravity 1 atomic mass unit = 1 u = 1.66 x 10-27 kg T (in kelvins) = T (in Celsius) + 273.15 VOLUME m3 1 Liter = 10-3 m3 = 10+3 cm3 SPEED m/s 1 mi/hr = 0.447 m/s = 1.47 ft/sec FORCE newton = N 1 N = 0.225 pound ENERGY & WORK joule = J 1 calorie = 4.186 J 1 J = 0.738 ft lb 1 electronvolt = 1.602 x 10-19 J, 1 BTU = 252 cal POWER watt = W 1 horsepower = 746 W = 550 ft lb/sec ANGLE radian = rad 1 revolution = 360 = 2π rad Derived Units: FREQUENCY hertz = Hz 1 Hz = 60 rev/min = 1 cycle/sec IMPULSE & MOMENTUM kg m/s = N S PRESSURE pascal = N/m2 1 atmosphere = 1.013 x 105 Pa = 14.7 lb/in2 SI prefixes: Power: 10-24 10-21 10-18 10-15 10-12 10-9 10-6 10-3 10-2 10-1 Prefix: yocto zepto atto femto pico nano micro milli centi deci Abbreviation: y z a f p n Power: 101 102 103 106 109 1012 m c d 1018 1021 1024 Prefix: deka hecto kilo mega giga tera peta exa zetta yotta Abbreviation: da h k M G T P E Z Y