Physics I Flashcards
Adding and Subtracting Vectors
Head to tail method
Component method
Force
any influence capable of causing a mass to accelerate
capacitors in series
inverse of the sum of inverses
Projectiles
falling bodies in two dimensions
Mass
Temperature
Time
Scalar
force with a pulley
F=mg/#ropes
Fnet=ma
Newton’s second law
Potential energy in a fluid per unit volume
PE=pgh (p is density)
equipotential lines are drawn
perpendicular to field lines
Capillar action
ability of a liquid to flow in narrow spaces without the assistance of external forces
what direction is the force of friction
opposite the direction of motion
Time in the air
(2Vy)/g
Center of mass
weighted average of mass distribution
field
invisible influence that can exert a force on a mass or charge
is mechanical energy conserved
yes, in the absence of non-conservative forces
Specific gravity
a ratio that describes how dense something is compared to water
SG=Dsubstance/Dwater
Action-reaction
Newton’s third law
two vertical lines of equal length
capacitor
Inertia
the ability of an object to resist a change in its velocity
A constant forces causes a
constant acceleration
current into a node=
current ot of a node
G is analogous to
K
non-conservative forces
friction, drag, air resistance
what is theta in calculating a magnetic field
angle between v and B
isolated system
no flow of matter or energy
heat energy
dissipated as heat, usually from a collision or from a current-carrying wire
G
6.67e-11 (m^3)/kg*s^2)
sin(0)
0
what type of current producing a sine wave
alternating
his analogous to
r or d
changing plate thickness causes what change to capacitance
none
Min potential energy of a pendulum
At the bottom of the arc
Static friction
occurs without sliding
m is analogous to
q
heat is energy transfer via
energy flow
for the same two surfaces, is kinetic or static friction more?
static friction is more
Kinetic friction
occurs with sliding
units of B in magnetism
Nc/Cm
kg/A*s^2
Q
ratio of charges
strength of gravitational field
g=Gm/r^2
Density
Degree of compactness of a substance
D=m/v
“exactly balanced”
equilibrium
equation for capacitance
C=Q/V
Period of a mass on a spring
T=2pi*sqrt(m/k)
tails of field lines point to
positive charge
Displacement
Momentum
Weight
Vector
What does a positive displacement versus time slope represent?
motion to the right
V= in a circuit
0
what always is true at equilibrium
net force is zero
energy transfer via force
work
PE(capacitor)= (2 equations)
1/2CV^2=1/2VQ
What value is changing with time?
y axis
Center of buoyancy
at the center of mass of the fluid displaced
AxBx*AyBy
Dot product
shorter line in a battery
negative
formula for resistance
R=pL/A
p-resistivity
L- length
A- cross sectional area
battery
electron pumps that push electrons onto the negative terminal
Force of friction
Ff=uFn=umgcos(theta)
u- for static or kinetic friction
equations for power
P=(deltaE)/t
P=W/t
P=Fdcos(theta)/t
gh is analogous to
V
Period of a pendulum
T=2pi*sqrt(L/g)
Elastic potential energy
potential energy stored in a compressed spring
PE=0.5k(deltaX)^2
increasing temperature on resistivity
linear increase
formula for torque
T=F*l
T=mgl
T=Frsin(theta)
Pascal’s Law
pressure is transmitted in all directions, undiminished, through a contained, incompressible liquid
change in pressure at any point in a confined, incompressible fluid causes the same change at every point
machines reduce
the force necessary to do an amount of work
diagonal circuit break line
switch
what happens to a dipole when exposed to an electric field
aligns with the field
two vertical lines of unequal length
battery
voltage is
electrical potential
Air resistance
the force exerted on projectiles or falling bodies due to actual physical collisions with air molecules
electric potential energy of a constant electric field
PE=qEd
Hooke’s law
F=k(deltaX)
DeltaX is the displacement of the spring from its equilibrium point
in what type of system is energy conserved
isolated
Action-reaction pairs
Bat hitting a ball
Balloon
Standing on the ground
strength of a point charge electric field
E=Kq/r^2
point charge fields depend on
distance
Unit of force
Newton
(kg*m)/s^2
static equilibrium
objects at rest
point charge fields are most similar to
gravity in space
Capacitor
store energy and charge by holding electrons on plates separated by a small distance
increasing dielectric strength causes what change to capacitance
increase
Normal force
Fn=mgcos(theta)
Tension
force in a rope, string, cable
negative charges in magnetism
south poles
increasing distance between plates causes what change to capacitance
decreases (increases voltage)
work-energy theorem
work=KE(final)-KE(initial)
rsin(theta) is always equal to
l
Hooke’s law is used for?
Springs
definition of voltage
amount of potential energy a system is capable of storing per unit charge
Ohm’s Law
V=IR
energy transfer via energy flow
heat
Range
Horizontal distance traveled
Vx*t
KE=
1/2mv^2
insulator
internal electrical charges do not flow freely
direct current
an electric current flowing in one direction only
force applied across a distance
work
(-) versus (+) charge
electrons versus deficiency of electrons
cos(90)
0
Adhesive forces
attractive forces between unlike substances
cling to surfaces
g is analogous to
E
Displacement
the shortest distance from A to B
Scalar
Has only magnitude
battery is an example of what energy
chemical
battery in series
add directly
force of a magnetic field=
qvBsin(theta)
what direction does current flow
opposite of electrons, negative to positive
Density of water
1g/cm^3
Scalar product
Dot product
what does a positive velocity versus time slope represent?
positive acceleration
Frequency
f=1/T
g
always 10m/s^s DOWN
Cross section area and air resistance
greater cross sectional area impacting the air means more air resistance
what should be set equal in fulcrum problems
torque
Optimal launch angle
45°
Straight line graph
Constant slope
Gravitational potential energy (near earth and in space)
Near earth: PE=mgh
In space: PE=(-Gm1m2)/r
Y values above the x axis
positiove
Exists at the center of mass
Center of gravity
Archimede’s Principle
any object displaces an amount of fluid exactly equal to its own volume or to the volume of whatever fraction of the object is submerges
The weight of the displaced fluid is exactly equal to the buoyant force pushing up on the object
sin(90)
1
electrical potential energy of a point charge electric field
PE=-Kqq/r
Min kinetic energy of a pendulum
At the max height
What does slope of a displacement versus time graph represent?
velocity
changing a magnetic field creates
electrical field
What are the conditions for a constant velocity?
No acceleration No net force No change in direction All forces sum to zero Equilibrium
Turbulence
although net flow is in one direction, there are random eddies, changes in direction and velocity
@increasing velocities
Center of gravity
point at which the resultant of the system of parallel forces formed by the weights of all the particles constituting the body passes for all positions of the body
open system
flow of energy and matter
cos(30)
sqrt(3)/2
superconductivity
zero resistance
Max kinetic energy of a pendulum
At the bottom of the arc
open switch
no electron flow
Universal law of gravitation
F=(Gm1m2)/r^2
An increase in speed of fluid occurs with
a decrease in potential energy or pressure, or both
The fraction submerged of an object is equal to
the ratio of object density to liquid density
closed switch
electrons flow
Field
an invisible influence capable of exerting a force on a mass or charge
energy
the capacity to do work
Is displacement a scalar or vector?
Is distance a scalar or vector?
Displacement- vector
Distance- scalar
resistor
limits the flow of electrical current
Cross product
Multiplication of two vectors in 3D space
Y values below the x axis
negative
What does slope of a velocity versus time graph represent?
acceleration
cos(0)
1
what do field lines represent
current flow
Gravity
a field that exists between any two objects with mass
Mass
a measure of an object’s inertia
cos(45)
sqrt(2)/2
Power=
IV
PE/m is equal to
voltage
Ideal fluid flow
no drag or friction between surfaces or between the molecules themselves
velocity at the base of an inclined plane
v=sqrt(2gh)
do machines change the work done
no
Non-linear graph
non-constant slope
magnetic lines flow from
north to south
positive work
by a system, same direction as velocity
cardiac output
stroke volume X heart rate
what is the torque of a force at the center of mass
zero
zig zag line
resistor
equations for instantaneous power
Pi=Fvcos(theta)
Max potential energy of a pendulum
At the max height
work is energy transfer via
force
Pedulum
any weight attached by a rode, string, wire, etc to a fixed overhead point and capable of freely swinging from side to side
resistance
drag in fluids or friction between solids
what is true of a dipole not signed with the electric field
has potential energy
semi-conductor
solid substance with conductivity between an insulator and most metals
Velocity
The speed of an object in a given direction
1L water is equal to
1kg
Force down an inclined plane
F=mgsin(theta)
equation for a point charge electric field
F=Kqq/r^2
longer line in a battery
positive
dynamic equilibrium
objects in motion at constant velocity
examples of equilibrium (5)
terminal velocity constant velocity objects at rest balanced fulcrums objects floating
constant electric fields are most similar to
gravity near earth
Poiseuille flow
exhibits laminar flow and has a leading edge that is parabolic
A constant acceleration causes a
linear change in velocity
non-linear change in displacement
what occurs over a resistor when current flows through it
voltage drop
negative work
on a system, opposite direction as velocity
cos(60)
0.5
Buoyant force
the upward force exerted by any fluid upon a body placed in it
Fb=pvg
current
amount of charge that flow past a fixed point per unit time
equipotential lines represent
areas of equal voltage
Magnetic field
Impulse
Torque
Vector
Cohesive forces
Between molecules of the same substance- tendency to resist separation
sin(60)
sqrt(3)/2
Fluid pressure
average force of the molecular collisions per unit area
P=pgh (p is density, h is depth)
charge on an electron
1.6e-19 C
alternating current
an electric current that reverses its direction many times a second at regular intervals
voltage increases with
distance
Apparent weight (of a submerged object)
the actual weight minus the buoyant force
Newton’s third law
whenever one object exerts a force (via contact or via a field) on a second object, the second object always exerts and equal and opposite force on the first object
work formulas
W=deltaE
W=Fdcos(theta)
||A|| ||B|| cos(theta)
Dot product
Acceleration down an inclined plane
a=gsin(theta)
increasing plate area causes what change to capacitance
increases
PE(elastic)=
1/2kx^2
Acceleration
any change in velocity (speed or direction)
moving electrons cause a
magnetic field
conservation of charge
universe has zero net charge
amount of work necessary to move a charge against an electric field
voltage
Simple Harmonic motion
anything that oscillates back and forth and can be represented by a sine wave graphically
When are speed and velocity equal?
Distance traveled is along a straight line
Friction
the resistance that one surface or object encounters while moving over another
OPPOSES SLIDING not motion
closed system
flow of energy, not matter
Shape and air resistance
less aerodynamic means more air resistance
Terminal velocity
object has stopped accelerating and the forces of gravity and air resistance are balanced
sqrt((2mg)/CpA))
Newton’s second law
acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object
Velocity and air resistance
increased velocity means more air resistance
dielectric
substance between the two plates in a capacitor
when does r=l
perpendicular
change in energy=
q+w
motion to the left
velocity versus time graph in lower right quadrant
negative velocity
conductor
allows the flow of electrical current in one or more directions
Surface tension
intensity of intermolecular forces per unit length at the surface of a liquid
“stationary”
equilibrium
force with a lever
F=mg(L1/L2)
Fair=mg
terminal velocity
PE(electrical)=
(kqq)/r
(r1m1+r2m2+r3m3+…)/mtotal
Center of mass
changing an electrical field creates
magnetic field
||A|| ||B|| sin(theta)
Cross product
Motion to the right
velocity versus time graph in upper right quadrant
positive velocity
chemical energy
energy contained within chemical bonds OR the energy stores due to the separation and/or the flow of electrons
capacitors in parallel
add directly
positive charges in magnetism
north poles
resistors in series
add directly
force with hydraulic lift
F=mg(h1/h2)=mg(A1/A2)
sin(30)
0.5
Laminar flow
flow in a pipe is in concentric sheets, each of which has a different velocity
fastest at the center and slowest at the interface with the wall
@low velocities
internal energy
internal vibrations and random motions of molecules within a system
Bernoulli’s Principle
K=P +pgh+0.5pv^2
P- pressure energy, random vibrational energy of molecules
pgh- potential energy
0.5pv^2- kinetic energy
Flow rate
Q=V*A
use cross sectional area
battery in parallel
highest voltage battery
Change
Work
Speed
Scalar
current through parallel resistors is related to resistance in what way
inverse
potential energy stored in a capacitor
U=.5QV
sin(45)
sqrt(2)/2
resistors in parallel
inverse of the sum of inverses
Force with a ramp
F=mg(h/d)
h- height
d- hypotenuse
Average velocity
(Vi+Vf)/2
units of power
watts (J/s)
I=
(deltaq)/(deltaT)
non-conservative forces cause what energy change
kinetic to internal
Vector product
Cross product
Newton’s first law
an object at rest stays at rest and an object in motion stays in motion if not acted upon by an imbalanced force
ME=
KE+PE
Vector
Has both magnitude and direction
