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PHYSICS FORMULAS
I. Motion
a. General
Velocity
v avg 
x
t
Straight line motion with constant acceleration
Acceleration
aavg 
 x  12 (v i  v f )t
v f  v i  at
v
t
 x  v i t  12 at 2
v f 2  v i 2  2a x
1
vavg  (v f  vi )t


2
II. Force
a. General
F  ma

III. Work
a. Done by constant force

WNet  FNet d(cos )
b. Equilibrium
F  0

b. Work-Energy Theorem
WNet  K.E.
IV. Energy
a. Kinetic energy b. Gravitational Potential Energy c.Elastic Potential Energy


K.E.  12 mv 2
Ugrav  mgh
Uelastic  12 kx2
d. Conservation of Mechanical Energy

M.E.i  M.E. f
e. Power
W
P
t
or
P  Fv
V. Momentum
a. General b. Impulse-Momentum Theorem c. Conservation of Momentum
p  mv
 p  Ft  mv f  mvi
pi  p f

VI. Angular Motion
a. Angular Displacement
b. Angular Speed
c. Angular Acceleration

s


 
 avg 
 avg 
r
t
t
d. Tangential Speed e. Tangential Acceleration f. Centripetal Acceleration
v2
v t  r
at  r
ac  t  r 2
r

g. Centripetal Force h. Newton’s Universal Law of Gravity i. Friction
Gm1m2
mvt2
Fk / s  k / sFN
Fg 
F

C


r 2 
r
j. General Torque


  Fd sin


VII. Fluid Mechanics
a. Mass Density
m

v
b. Buoyant Force
c. Pressure
F
P
A
FB  Fg  mg
d. Fluid Pressure as a Function of Depth
e. Bernoulli’s Equation
P  Po  gh
constant  P  12 v 2  gh



VIII. Heat and Thermodynamics
a.Conservation of Energy b. Specific Heat Capacity c.Ideal Gas Law

 Q  Cp mT
PV  nRT
P.E. K.E. U  0



d. Work done by a Gas
W  PAd  PV
f. Combined Gas Law
P1V1 P2V2

T1
T2
st
e. 1 Law of Thermodynamics
U  Q  W

g. Efficiency of Engines
W
eff  out
W in
IV. Harmonic Motion
a. Hooke’s Law b.Period of Simple Pendulum c.Period of Mass-Spring


m
L
Felastic  kx
T  2
T  2
K
g
d. Period and Frequency
1 2
T 
 f



X. Sound
a. Intensity
b. Velocity on Rope
FT
p
v
I
2
m /L
4r
c. Harmonic Series
Vibrating String Open Pipe at both Ends
Pipe Closed at one end
nv
nv
nv
fn 
fn 
fn 
n  1,3,5,...


2L
2L
4L
XI. Waves
a. General Speed
v f 

XII. Light
a. Speed

C f 



d. Index of Refraction
c
n
v

g. Destructive Interference
d(sin)  (m  12 )


b. Mirror
1 1 1 2
  
do d i f R
e. Snell’s Law
c. Magnification
h' d
M  i
h do
f. Critical Angle
n
sinC  r
ni
ni sini  nr (sinr )

h. Constructive Interference
d(sin)  m

XIII. Electricity
a. Electric Field Strength
1. General
Felecrtic  qE
2.Between 2 charges 3. Point Charge
qq
q
Felectric  kC 1 2 2
E  kC 2
r
r
b. Electric Potential
1. Uniform Electric Field

Uelec  qEd

2. Pair of Charges
qq
U elec
 kC 1 2
r
c. Potential Difference
1. General
U electric

or U
V 
 qV
q
2. Uniform Field 3. Point Charge and Infinity
q
v  Ed
v  kC
r

d. Capacitance
1. General 2. Parallel 3. Work to move charge across capacitor

Q
A
1
C
C
 o 
W  CV 2
V
d
2
e. Potential Energy Stored in a Capacitor
P.E.elec  12 QV



f. Electric Current g. Ohm’s Law h. Electric Power i. Battery Voltage
Q
 I 
V  I  R
P  IV
V    IR
t
j. Resistance
1. In Series
2. In parallel
3.Resistance

 1

1
1
1

 

 ...
L
Req R1 R2 R3
R
Req = R1+ R2+ R3 + …
A
k. Capacitors

1. In Series
1
1
1
1
 

 ...
Ceq C1 C2 C3

2. In parallel
Ceq  C1  C2  C3  .....
IX. Magnetism
a. Magnetic Field Strength
b. Magnetic Field Around Wire

Fmag
I
B
or Fmag  qvBsin 
B o

qV sin
2r
c. Force on current-carrying conductor perpendicular to magnetic field
Fmag  BIl sin



d. Faraday’s Law of Magnetic Induction
AB cos  

  emf  N
N
 NBlv
t
t
XV. Quantum
a. Rest Energy and Mass
b. Binding Energy of Nucleus
2
ER = mc
c. Half-Life
0.693
T1 2 
EBIND = mc2

d. Energy of light Photon
E  hf

e. Kinetic Energy of photoelectron(Work function) f. Radioactive
Decay Rate
E  KE  hf Wo

g. Wavelength and Frequency of Matter Waves
h
h
E
 
f 


p mv
h
XVI. Modern
a. Time Dilation

t 
v2
L  Lo 1 2
c
v2
c2


t

 No e
b. Length Contraction
to
1
N  No e


t ln 2
T1/ 2