Heat
Q = mcΔT for temperature rise
Q = mL for phase transitions
Substance
Substance
Specific Heat, c
(cal/g °C)
6.96
1.00
0.580
0.497
0.490
0.215
0.0925
0.0558
0.0301
Air
Water
Alcohol
Steam
Ice (-10 °C)
Aluminum
Zinc
Silver
Gold
Water
Alcohol
Silver
Zinc
Gold
Helium
Fusion, Lf
(cal/g)
80.0
26
25
24
15
-
Vaporization, Lv
(cal/g)
540
210
556
423
407
5.0
Electrostatics
F = kq1q2/r2
F = qE
E = –ΔV/Δx
Ue = qΔV
1eV = 10-19 J
Electric circuits
ΔV = IR
P = ΔE / Δt = IΔV = I2R = V2/R
I = Δq/Δt = ΔV/R
R = ρl/A
Name
Voltage
Source
Symbols
Unit
ΔV
Volt (V)
Resistor
R
Ohm (Ω)
Capacitor
C
Farad (F)
Diode
none
none
Rseries = R1 + R2 + …
1 / Rparallel = (1/R1) + (1/R2) + …
Typical examples
9 V (cell phone charger); 12 V (car); 120 VAC
(U.S. wall outlet)
144 Ω (100 W, 120v bulb); 1 kΩ (wet skin)
RAM in a computer, 700 MF (Earth)
light-emitting diode (LED); solar panel
Units, Conversions and Constants --------------------------------------------------------------------------------Metric units
‘n’ = nano, 10-9 (1 nm = 10-9 m)
‘µ’ = micro, 10-6 (1 µm = 10-6 m)
‘m’ = milli, 10-3 (1 mm = 10-3 m)
‘k’ = kilo, 103 (1 km = 103 m)
‘M’ = Mega, 106 (1 Mm = 106 m)
‘G’ = Giga, 109 (1 Gm = 109 m)
Conversions
Constants
1 meter = 3.28 ft.
1 mile = 1.61 km
1 lb. = 4.45 N
G = 6.672×10–11 N•m 2/kg 2
me = 9.11 x 10-31 kg
mp = 1.67 x 10-27 kg
qe = qp = 1.6 x 10-19 C
Waves and Light -------------------------------------------------------------------------------------------------------T=1/f
v = c/n
v = λf
vsound = 331.4 m/s + 0.6T
n1sinθ1 = n2sinθ2
1/f = 1/do + 1/di
c = 3 x 108 m/s
Motion 1D -----------------------------------------------------------------------------------------------------------------vavg = Δx / Δt
aavg = Δv / Δt
Δx = v0t + ½at2
Δv = at
v2 = v02 + 2a(Δx)
Δx = xfinal – xinitial
Δ(anything) = final value – initial value
g = -9.81 m/s 2 ≈ -10 m/s 2 (upward is positive direction)
Projectile Motion -------------------------------------------------------------------------------------------------------sin(θ) = b/c → b = c • sin(θ)
cos(θ) = a/c → a = c • cos(θ)
tan(θ) = b/a → b = a • tan(θ)
Δx = vxt
Δy = v0yt + 1/2gt2
v2fy = v20y + 2gΔx
c
θ
b
a
g = -9.81 m/s 2 ≈ -10 m/s 2 (upward is positive direction)
Note: vx does not change when neglecting air resistance
Force-----------------------------------------------------------------------------------------------------------------ΣF = ma
ΣFx = max
ΣFy = may
Fg = mg
P = F/A
Momentum and Energy Conservation--------------------------------------------------------------------------Σpi = Σpf
p = mv
K = ½ mv
2
Usp = ½k(Δx)
Ug = mgh
W = F·Δx
P = ΔW / Δt (change in energy/ time)
2
Δp = FΔt
1 J = 1 N•m
1 W = 1 J/s
1 food Calorie = 4180 J