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gravitational force between two objects
Gm1m2/r^2

what keeps an object in its circular pathway?
centripetal force


work done by nonconservative force
=change in Energy (change in potential energy plus change in kinetic energy)

when can we say work is done in a system?
when volume of the system is changed due to an applied pressure.

work
 Fdcos (theta)
 area under PV graph

when a gas expands is work positive or neg?
work is positive (work was done by the gas)

isochoric
same as isovolumetric

power
 work done per unit time
 watt
 J/s

work energy theorem
work done is equal to change in KE

first law of thermodynamics
change in internal energy = heat transferred into the system  work done by the system

mechanical advantage
ratio of magnitudes of force exerted on an object by a simple machine to the force actually applied on the simple machine

efficiency
 work output/ work input
 work input is the product of (effort)(effort distance)
 output (load x load distance)

kelvin to celsius
K=C+273

Fahrenheit to Celsius
F=(9/5)C+32

thermal expansion
change in length= (coefficient of linear expansion) (original length) (change in temp)

isolated system
 not capable of exchanging energy or matter
 total change in internal energy is zero
 insulator (calorimeter)

closed system
 capable of transferring energy
 movable pistons and gases are examples

state function
 independent of path taken to reach a particular equilibrium state
 function of only the current equilibrium state of a system
 Pressure, density, temp, volume, enthalpy, internal energy, Gibbs free energy, and entropy.

how does one change the internal energy?
 increasing the temperature in the system
 (increasepos, decreaseneg)

when is work positive for a system?
 work is positive when system expands
 work is neg when system compresses

1 cal is how many joules
4.184

convection
 transfer of heat by physical motion of fluid over material.
 only liquids and gases

radiation
transfer of energy by electromagnetic waves, can transfer energy through vaccum

specific heat
 amount of heat required to raise 1 g of substance by one degree Celsius or kelvin
 for liquid that is 1cal/(g K) or 4.184J/(g.K)

heat equation
 q=mc (change in temp)
 c=specific heat)

which has greater kinetic energy at the same temp: liquid or solid
even though liquid water has greater number of microstates (increase freedom of movment), KE is the same as solid water at same temp.

equation for heat during phase change
 q=mL
 (m is the mass of substance)
 L=constant




units for entropy
 J/ (mol.K)
 entropy of the universe is always increasing

fluid characteristics
ability to flow and conform to shape of the container



specific gravity
when density of fluid is compared to that of pure water 1g/cm^3

what is pressure in terms of force and area?

what is the pressure of air?
1.013 x 10^5 Pa=760 mmHg=760 torr=1atm

hydrostatic pressure
p0+pgz

force of buoyancy
density of fluid (V fluid displace) (g)

cohesion vs. adhesion
 cohesion, attractive force that molecule of liquid feels toward other molecules of same liquid
 adhesion: attraction between water and another substance, backwards meniscus

flow rate and radius and pressure gradient
 poiseuille's law
 flow rate is proportional to 4th power of radius, inversely proportional to pressure gradient

continuity equation
vA=vA

bernoulli's equation
P+1/2pv^2+pgh=P+1/2pv^2+pgh

