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translational motion:
distance, velocity, acceleration. time
x = x_{0} + v_{0}t + (1/2)at^{2}

translational motion:
velocity, acceleration and distance
v^{2} = v_{0}^{2} + 2ax

translational motion:
velocity, acceleration and time
v = v_{0} + at

how does a projectile stay in motion? what keeps it in motion?
inertia

peak height of a projectile
v_{0} = sin(0)  sq.rt.(2gh)

horizontal distance traveled of a projectile
x = vt . cos(0)

peak velocity
no velocity, but acceleration = 10

PE and KE of projectile object at its peak
 PE is maximized
 KE is minimized
(energy must be conserved)

projectile path is independent of....
mass

two objects launched with the same velocity will...
hit the ground at the same moment

what determines the time of flight?
vertical velocity

range of projectile is maximized at what angle from the horizontal?
45^{0}

symmetry of projectile says what? (speed wise)
upward mirrors downward 
initial speed = final speed

air resistance is greater on (surface area, shape, and speed)
 larger surface area
 irregularly shaped
 greater speed

does mass affect force or path of air resistance
force = no
path = yes

how does greater mass affect air resistance
force is the same, so it decreases acceleration
(F=ma)

centripetal force (equation)
F = m . v^{2}/r

inertia
tendency of an object to stay in present state of motion
(keeps projectile in motion)

law of universal gravitation
F = G(m_{1}m_{2})/r^{2}

friction points in what direction?
always parallel to surface

equation for torque
t = F r sin0

if the board has mass, what do you do with torque?
F=mg at center of board

equation for work (not for gases)
W = Fd cos0

what direction is friction (relative to work)?
friction does negative work!

work done lifting an object
W = Fd = mg x h

what is gravitational potential energy?
work done by gravity:
change PE = W

energy and power
energy = work + heat
so, P = (w + q)/s

1 revolution is equal to
2 pi r

equation for angular momentum
L = l x m x v
l = lever arm, mv = linear momentum

elastic collision
mechanical energy is conserved

inelastic collision
mechanical energy is lost to internal energy (heat)

perfect inelastic collision
2 objects stick together

reverse inelasitc collisions (object dissipates into 2 sep. objects). In what direction do they travel
opposite to each other

ex: man standing on a board and jumps off
what do you need to consider when determining their final positions?
move in opposite directions
consider their centers of gravity

what is impulse?
change in momentum

Machine: inclined plane (how is work minimized?)
straight up: W = ugh
ramp: W = mg x sin x h

What is theta equal to in the ramp
height of ramp / distance of the ramp
the greater the distance (d) the smaller the angle, the less work needed

Machine: lever (torque)
what does F need to equal to lift mass?
F = mg in opposite direction

How do you decrease the force required to life the object?
increasing the lever arm
(doubling lever arm, reduces force by a factor of 2)

In a pulley, what is the tension in the rope?
constant
Tension = Force

In a double pulley system, what is the force required to lift mass m?
F = T
T = 2mg
F = (mg)/2

alpha decay
2 protons, 2 neutrons

traveling of alpha particle
not far
stopped by skin, paper

beta decay
expulsion of an e^{}

positron
B+ is emitted (1 atomic #)

electron capture
gain e^{} (1 atomic number

frequency of a gamma particle
high frequency particle

rest mass energy
E = mc^{2}

fussion combining 2 (?) from (?)
combining 2 nuclei
from a heavier nucleus

fission
splitting a single nucleus into 2 lighter nuclei

where does energy for fusion and fission come from?
mass defect

density formula
density = m/v

density constant for gases and liquids?
constant for liquids and solids
change for gases, because they are compressible

What is specific gravity?
density of a substance compared to density of water

so specific gravity of water is
1

formula for fluid pressure
P = F/A

Do fluids at rest have uniform density in a sealed container?
yes

What is the pressure experience by fluids at rest with uniform density?
P = density x g x y
y = depth of fluid

Where is pressure greatest for a fluid at rest?
greatest depth (P=pgy)

What if you have many fluids layered in a sealed container?
P = (pgy)_{1} + (pgy)_{2} + (pgy)3...........

What is the pressure of a fluid at rest with uniform density in an open container
add atmospheric pressure to density x g x y

hydraulic lift (equation)
pressure is transferred completely:
F_{1}/A_{1} = F_{2}/A_{2}

What is the velocity of a fluid flowing (if you don't know rate or area)?
v = sq.rt (2gh)

buoyant force
upward force acting on a submerged object

what is buoyant force equal to? (not equation)
weight of fluid displaced by submerged object

equation for buoyant force
F_{B} = (density of fluid) x (volume) x (g)

floating object 
submerged portion of object =
density of object/density of fluid

How much of an object will float in water if its specific gravity is 0.4?
60%

does buoyant force change with depth?
No

What is the apparent mass on an object (when it is submerged)?
mass of the fluid displaced
thats why we weigh so little in water

equation for fluid flow
Q = (area)(volume)

does fluid flow faster in a wider pipe, or a more narrow pipe?
narrow

ideal fluid flows at a constant rate
K = Pressure + (density)(g)(h) + (1.2)(p)(v^{2})
K is constant, specific to fluid in a flow

surface tension and temperature
increase temperature = weaker surface tension

formula for stress
force/area

formula for strain
change in dimension/original dimension

what are stress and strain
stress is done on an object
strain is how the object responds

modulus of elasticity
stress/strain

What is Coloumb's law? (equation) What does it mean?
describes force between two charges
F = k (q1q2) / r
k = 9 x 10^{9}

Coloumb's law resembles what? But?
gravitational force (G)(m _{1}m _{2})/(r ^{2})
 but, gravitational force is attractive
 electrical force is repulsive

electric field  in what way are the lines drawn? What does the length of the line indicate?
(+) > ()
length = strength
(smaller is stronger)

What is the electric field created by charge Q?
E = k x (Q)/(r^{2})

What is the force felt by charge q in the electric field E?
F = E x q

What makes and feels the field?
Q makes the field
q feels the field
[F = k x (Qq)/(r^{2})

What is the potential energy of of the charge in electric field?
Potential energy (U) = force x displacement (like ugh)
U = Eq x h

How does potential energy change when moving perpendicular to electric field?
doesn't change
same way that moving parallel to surface of the earth doesn't change gravitational potential energy

What is an electric dipole?
created by 2 opposite charges with equal magnitude

(+) and () fall/rise to lower/higher potential?
+ charge falls to a lower potential
 charge rises to a higher potential

high/low potential and +/ potenital
 high potential = + potential
 low potential =  potential

How do we measure movement of a charge?
current (A)

So, what is current? (How is it measured)
Coloumbs/second

Current flows in what direction (relative to potential energy)
current flows from high potential to low potential

In what direction does current flow (relative to electron flow or electron velocity)?
current moves in opposite direction of e^{} flow

conducting electricity: what are good conductors and poor conductors?
 good = allow e^{} to flow freely [metals]
 poor = hold e^{ }tightly in place [resistors]

What is induction?
charging a conductor

circuit equations: current, voltage, resistance, capacitance
V = IR
I = Q/t
C = Q/V

what is capacitance?
ability to store charge per unit voltage [Q/V]

voltage is the same thing as...... and it depends on
potential energy
depends on distance

plates that are further apart will have greater/less voltage and capacitance?
greater voltage
less capacitance

What is a capacitor?
temporarily stores energy in a circuit

What is the separation of charges in a capacitor?
emf between the plates

what is resistance?
resistance to flow of charge

resistance is directly proportionate to what?
length of wire
[R = density x (length/area)]

resistance and temperature
resistance increases with temperature
[thermal oscillations impede with flow]

Kirchoff's Rules:
 amount of current flowing in and out
 voltage around the circuit
battery
 amount of flow in = amount of flow out
 votalge around any path in circuit must sum = 0
 battery adds energy to circuit

How does battery add energy to the circuit?
increases voltage from one point to another
(emf = voltage added)

Diaelectric constant (K)
substance between plates of a capacitor
 must be insulator to separate charge
 resists creating EF, in order to store energy

Resistors in series/parallel
what is constant?
series = add [current is constant]
parallel = 1/R [voltage is constant]

what is the terminal voltage? (equation)
V = emf  IR

AC Current  what's going on?
e^{} don't move in one direction,
they oscillate back and forth

maximum current and maximum velocity in an AC Current
V_{max} = sqrt.(2) x V_{max}
I_{max} = sqrt.(2) x I_{max}

What creates a magnetic field?
charging electric field
currents (moving charges) creates the magnetic field

+ and  of electric field corresponds to what in magnetic field?
north and south
north = + and south = 

In what direction do magnetic lines point?
north > south

Doess a stronger magnetic field have closer lines, or further apart?
closer lines = stronger fied

How does the KE of a particle moving through the magnetic field change?
no work done by the magnetic field, means no change in KE due to the magnetic field

What is magnetic force?
F = q x V x B x sin(0)

force is applied in what direction relative to both velocity and magnetic field
force is perpendicular to both velocity and magnetic field

What is the work done by magnetic force?
no work:
because it's perpendicular to velocity

What way does magnetic field act?
like centripetal force (mv^{2}/r)
because charged particle moves in a circle

What will move through a magnetic field with a smaller radius: a proton or an electron
electron:
because it has smaller mass [F = mv^{2}/r]

Right Hand Rule
thumb = direction of current
fingers = direction of magnetic field
palm = direction of force

What results from a change in magnetic field?
an electrical field

What happens to the mechanical energy in a magnetic field when it is changed and creates an electric field?
mechanical energy to create the field is dissipated as heat

What is the magnetic flux?
number of magnetic fields running through the loop

what does change in magnetic flux do?
induces an emf

What is a magnetic field generated by?
a moving charge

moving charge experiences what when moving through a magnetic field?
force = qvBsin0

In what direction is this force?
perpendicular to velocity and magnetic field (B)

At equilibrium, in an electric and magnetic field, what is the net force acting on a particle?
0
force from electric field = force from magnetic field
Eq = qvBsin(0)

How can we find the acceleration or distance of a particle traveling through an electric or magnetic field
F = ma
set force (Eq) or (qvbsin) = mass x acceleration
distance = (1/2)at^{2}

