Physics and Math Flashcards
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sin of an angle = opposite over hypotenuse, cos of an angle =adjacent over hypotenuse, tan of an angle = opposite over adjacent
pythagorean theorem
x^2 + y^2 = V^2
force definition
vector quantitiy that is experienced as a pushing or pulling on an object, represented in newtons (N) equal to (kgxm)/s^2
gravitational force equation
Fg = Gm1xGm2/r^2 where G=universal gravitational constant 6.67x10^-11
friction
type of force that opposes movement of objects, either static or kinetic
static friction (fs)
between a stationary object and surface upon which it rests, equation is 0</=fs</=usxN where us is coefficient of static friction and N is magnitude of normal force
normal force (N)
component of force between 2 objects that is perpendicular to the plane of contact between the object and the surface it rests
kinetic friction (fk)
fk=ukxN where uk is coefficient of kinetic friction and N is noral force,
are wheels rolling on a road kinetic or static friction?
static, unless the tire begins to slide on an icy patch
which is always greater, static or kinetic friciton
static
weight (Fg) formula
Fg=mg mass x acceleartion due to gravity which is normally 9.8 m/s2
4 basic kinematic equations
v = v 0 + a t.
Δ x = ( v + v 0 2 ) t.
Δ x = v 0 t + 1/ 2 a t 2.
v^ 2 = v o^ 2 + 2 a Δ x.
circular motion equation
Fc = mv^2/r
torque equation
T = rxF=rF sin(angle)
torque in counterclocwise condition is ___, while clockwise is ____
positive, negativ
kinetic energy equation
K = 1/2 mv^2
gravitational potential energy formula
U=mgh
Elastic potential energy equation
U=1/2kx^2 where k is spring constant
total mechanical energy equation
E = U + K (potential plus kinetic)
conservative forces
forces that are path independent and do not dissipate energy, most common are graviational and electrostatic, does not include energy “lost” from a system in the form of dissipated heat from friction for example
nonconservative forces are path _____
dependent
work vs energy
work is not a form of energy itself but a process by whcih energy is transferred from one system to another even though both are represented in J
work equation
fore x distance cosign theta
when gas expands, we say work was done byt the __ and the work is ___, when gas is compressed, we say….
gas, positive, … work is done onto the gas and the work is negative
power definition
rate at which energy is transferred from one system to another
power equation
P = W/t (Work over time), measured in watts which is J/s
zeroth law of thermodynamics
when one object is in equilibrium with a second, and a second with a third, then the first is in equilibrium with the third as well
temperature
measure of average kinetic energy of molecules that make up a substance
thermal equilibrium
when there is no net heat flow between two objects in thermal contact
third law of thermodynamics
entropy of a perfectly organized crystal at absolute zero is zero - there are no negative temperatures
absolute zero in kelvin and C
0 and -273, the two units are contiguious
thermal expansion formula
deltaL=aL(deltaT) where a is coefficient of linear expansion, L is original length, and T is change in temp in K or celsius, doesn’t matter
volumetric thermal expansion formula
deltaV=BV)(deltaT) where B is coefficient of volumetric expansion
first law of thermodynamics
change in total internal energy of a system is equal to the amount of energy transferred inthe form of heat to the system,minus the amount of energy transferred to the system in the form of work.
second law of thermodynamics
objects in theraml contact and not in thermal equilibrium will exchange heat energy such that objects with higher temp will give off heat energy to lower temp until both are at equilibirum, heat measured in J
types of heat transfer
conduction - direct transfer of energy from molecule to molecule thru colllisions, requiring direct physical contact between the objects,
convection - transfer of heat by physical motion of fluid over a material, only liquids and gases can transfer this way,
radiation - transfer of energy thru electromagnetic waves
cspecific heat
amount of heat energy neededto raise 1 gram of a substance by 1 degree celcius or 1 unit kelvin.s
specific heat of water
1 cal/(gxK)
calorimetry formula
q=mc delta T, where m is mass, c is specific heat, and delta T is change in temp in celsius or kelvin, only works when there is a temp change so not during a phase change
temp will not rise until all molecules being acted on have…
…udergone their phase change
in phase change increasing heat and chaging state increases ____ energy, but not ___ energy
potential, kinetic
equation for change in heat during a phase change
q=mL where m is mass of substnace and L is heat of transformation or latent heat of a substance
both liquids and gases are considered
fluids
fluids vs solids
btoh can exert forces perpendicular to their surface, but only solids can withstand shear (tangential forces), fluids can impose large perpendicular forces making falling into water from a significant height as painful as falling onto solid surface
density formula
p=m/V
is a liter equivalent to m^3? What is the density of water
NO, 1 g/cm3 = 1000 kg/m^3
weight of any volume of a given substance with a known density calculation
Fg = pVg
specific gravity eequation
SG = P/1 gram/cm^3
specific gravity definition
a variable used to compare density of fluid to that of pure water at 1atm and 4 degrees C
pressure equation
P=F/A measured in Pa
pressure distribution
pressure is same at all points and thus scalar quantity without direction
absolute hydrostatic pressure
total pressure exerted on an object submurged in fluid
absolute hydrostatic pressure equation
P=P0 + pgz (P0 is ambient pressure pressure at surface, p is density, g is acceleration due to gravity, and z is depth
pascal’s principle
for fluids that are incompressible a change in pressure will be transmitted undiminished to every portion of the fluid and to the walls of the containing vessels
pascal’s principle equation
P = F1/A1 = F2/A2
archimede’s principle
a body wholly or partially immersed in fluid willbe buoyed upwawrds by a force equal to thew eight of the fluid that it displaces
archimede’s principle formula
F buoy = p fluid x V fluid displaced x g = p fluid V submerged x g
cohesion and adhesion
cohesion creates surface tension, attactive force a molecule of liquids feels toward other molecules of the same liquid, adhesion is attractive force toward molecules of some other substance,
