Physics Flashcards
types of heat transfer
- conduction
- convection
- radiaton
Radiation heat transfer consists of
heat transfer due to electromagnetic waves
conduction heat transfer consists of
heat transfer due to direct contact
Conduction heat transfer consists of
heat transfer due to bulk flow movement.
Pressure at a given depth is called
hydrostatic pressure
Gases and Liquids are what kind of material?
Liquids
Density definition
Mass/volume
density of water is what?
1 g/mL = 1 g/cm^3 = 1 kg/L
Define specific Gravity
density of some liquid / density of water.
specific gravity = density of liqid/density of water
specific gravity of water is 1
Archimedes principle: define
the buoyant force on an object= weight of the fluid displaced by the object
Fb= weight displaced= ( mass displaced)(g) = ( density of fluid)(Volume submerged)(g)
What are the situations when comparing Fb to Weight such that it will float, sink or rise upward.
when FB = W , the object will float
when FB > W, the object will rise upward
when FB < W, the object will sink
Define hydrostatic pressure
if you apply pressure on a liquid, the pressure is transmitted equally to all parts of the liquid ( this is called pascal’s law)
Gauge Pressure
pgh because it igmore the atmosphereic pressure above the fluid….. it measures the amount of pressure beneath the surface.
Absolute pressure
is basically the pressure of something submerged in the ocean = pgh + atmospheric pressure
Pabs=Po + pgh
Continuity Equation
A*V=constant.
volume rate of a fluid is constant.
Surface tension is caused by what?
due to the attraction between molecules of the solvent.
Surface tension is caused by what?
due to the attraction between molecules of the solvent.
Stress definition
pressure exerted on an object F/A
Strain definition
the deformation of the object in the direction of the applied force divided by the original length
strain = Change in length/ inital length
Thermal expansion coefficient
alpha
when objects are cooled down or expanded, the object changes shape.
change in length = aloha * inital length * change in temperature.
MNEUMONIC + looks like alot
Chnage in volume Beta = 3* alpha
what do liquids and solids share in common and that seperates gases?
solids and liquids= incompressible
gases= compressible.
Adiabatic means what
- no heat transfer therefore it affects the internal temperature.
words to look for : quickly and rapidly
in an adiabatic compresion, temperature will…
increase
in an adiabatic expansion, temperature will
decrease
If the image is at infinity , then where is object
the object is at the focal length ,f
what is the formula for pressure and its units
Pressure = force / area
N/m^2 = pascal
Absolute pressure
P=P0+ pgauge
Po is not always 1 atm, it depends on the system
Pgauge= P-Patm = ( Po+pgz) - Patm
when Po=Patm
that is only when Pgauge = pgz
Absolute pressure aka hydrostatic pressure
P=P0+ pgauge
Po is not always 1 atm, it depends on the system
Pgauge= P-Patm = ( Po+pgz) - Patm
when Po=Patm
that is only when Pgauge = pgz
the specific gravity will indicate how much of the object is submerged
example if the specific gravity is 0.92 that means 92 % of the object is submerged under the water.
Papple/pwater = 0.92
Apparent weight in fluids
Fg-Fb= apparent weight in newtons
Force by gravity - force by bouyancy
Viscosity
unit in pascal seconds
- measure of internal resistance
- how resistance
Viscosity
unit in pascal seconds
- measure of internal resistance
- how resistance to flow is something
honey is the most viscous
- THINK DRAG IN FLUID
Flow rate definition
volume per second
this is a constant for a closed system and is independent of changes in a cross sectional area
Efficency definition
= ( Work out )/Work in
= ( Load * Load distance)/(Effort*effort distance)
Example - a pulley needs to be raised 3 meters who has a 10 N load there are 2 pulleys. the machine is 50 percent efficient.
effort distance - 2 pulleys * 3 = 6 m
solve for effort!
0.5 = ( 10*3)/( efffort * 6)
Efficency definition
= ( Work out )/Work in
= ( Load * Load distance)/(Effort*effort distance)
Example - a pulley needs to be raised 3 meters who has a 10 N load there are 2 pulleys. the machine is 50 percent efficient.
effort distance - 2 pulleys * 3 = 6 m
solve for effort!
0.5 = ( 10*3)/( efffort * 6)
bernouili equation
P1+1/2pmv^2+ pgh=P2+1/2pmv^2+ pgh=
P+pgh= static pressure
1/2 pv^2 = dymanic presure
if static pressure increases, then dynamic pressure decreases and vice verda.
P1 = energy density… Increase pressure therefore increase energy
speed of sound is what
343 m/s
and it changes as it travels though different mediums.
it travels fastest through solid –> liqiud and slowest in gas.
density defintion
mass/volume
1g/cm^3 = 1000 kg/m^3
Lyman series is what
lower in wavelength but INCREASE frequnecy …. ultraviolet
it goes down to n=1
Balmer series goes down to what orbiral level
n=2 COLOR ( partially visible)
If a test charge is positive (+) what direction is the force and the Electric field?
Force and the electric field are in the same direction
F=qE
If a test charge is negative, what direction is the force and the electric field?
Force and the electric field is in opposite directions
F=qE.
Force on a moving charge equation
Fb= qVBsin(theta)
Fb=ILBsin(theta) on a wire0
Use the right hand rule ..
Thumb = velocity
Finger = lines
Palm=force
Back of palm is used for negative charge
Magnetic Fields equation for a straight long wire
B= ( Uo I)/(2Pir)
Unit is tesla
Magnetic fields equation for a loop of current carrying wire
B= ( Uo* I ) / ( 2r)
magnetic field unit
T = tesla = Ns/MC =
Electric potential
positive test charge will move spontaneously from high potential to low potential.
Negative test charge will spontaneously move from low potential to high potential.
Poiseuille law
Q= ( pi r^4 delta P)/ ( 8nL)
flow rate is directly prrportional to change in pressure and radius to the 4th power
When a critical speed is exceeded what happens?
flow becomes turbulence and it forms eddies
when critical speed is not exceeded what happens
flow is laminiar
Specific gravity indicates the percent of volume is submerged
Example 0.92 specific gravity = 92 % of its volume is submerged
therefore any object whose specific gravity is less than 1 will float in water
Specific gravity indicates the percent of volume is submerged
Example 0.92 specific gravity = 92 % of its volume is submerged
therefore any object whose specific gravity is less than 1 will float in water
aA + bB -> cC + dD what is the rate
rate = k(A)^x * B^y
x and y are determined experimentally only
Mechanical advantage defintion
ratio of output force generated given a particular input force
Efficiency -
ratio of useful work performed by a system compared to work performed on a system.
= work out/work in = ( loadload distance)/( efforteffort distance)
dispersion of light
dispersion involves the breaking up of polychromatic light into its components
if light is monochromatic and it enters through a prism, refraction happens.
Pascal’s principle
pressure will remain constant - force adn area will change to accomodate
P=Force / Area
current = charge /time
max charge = current * time
It=nF
MNeumonic “ it is enough already- no more plating”
F= faradays’ constant = 96000
n- moles plated
I= current
t=time
max copper lating will need max time and current
Disproportionation reaction
When reactant and product have different oxidation state.
Cl2+h20 –> HOCl + Cl - + H+
Cl 0 —> Cl +1 and Cl -
No element appeaks with different oxidation state in 2 products see chapter 11 chem in kaplan q12 discrete questions.
Disproportionation reaction
When reactant and product have different oxidation state.
Cl2+h20 –> HOCl + Cl - + H+
Cl 0 —> Cl +1 and Cl -
No element appeaks with different oxidation state in 2 products see chapter 11 chem in kaplan q12 discrete questions.
0 ordered reaction
aA + bB –> cC + dD
rate = k[A^0][B^0] = k
k has units of M/s
- not concentration dependent - only temperature and addition of a catalyst important
First ordered reaction
aA + bB –> cC + dD
rate = k[A^1]
or rate =k[B^1]
k has units of s^-1 ‘
Example: radioactive substance
Ln (A) vs t graph has a negative slope
First ordered reaction
aA + bB –> cC + dD
rate = k[A^1] [B^1]
or rate =k[B^2] or rate = k[A^2]
k= has units M^-1 s^-1
1/A vs t slope is positive
A long straight wire carries a current toward the top of the page. A proton moves with velocity 2x10^4 towards bottom of the page and to the left of the wire. The magnetic force on the proton is.:
A. Out of page
B. Into Page
C. Toward the left
D. Toward the right
o o || xx
oo || xx
o o || xx
first figure out the B field.
Next do F=qvbsin(theta)
B into page, V=down.. use thumb, index and middle fingers all perpendicular and you will see the F is LEFT therefore the correct answer is C.
A long straight wire carries a current toward the top of the page. A proton moves with velocity 2x10^4 towards bottom of the page and to the left of the wire. The magnetic force on the proton is.:
A. Out of page
B. Into Page
C. Toward the left
D. Toward the right
o o || xx
oo || xx
o o || xx
first figure out the B field.
Next do F=qvbsin(theta)
B into page, V=down.. use thumb, index and middle fingers all perpendicular and you will see the F is LEFT therefore the correct answer is C. \
One side open one side closed pipe n=
n= odd harmonic
3rd resonande = 5th harmonic
n=1,3,5
open both sides wipe
n=1,2,3
Need to know actual mass to figure out half life
1 -> 1/2 —-> 1/4 —> etc etc
How do beta and gamma radiation differ?
Gamma radiation - high energy photon lacking charge
beta radiation = electron
electron will get deflected by a magnetic/electric field because it is charged.
Gamma radiation - uncharged therefore no deflection with the magnetic / electric field.
N=c/v
n1 sin theta 1 = n2sin theta 2
when going from low index of refraction to high index of refraction the light ray bends towards the normal when entering the glass.
think about a higher index of refraction as a more viscous substance. N2>n1 therefore theta 2 < theta 1
When going from high index of refraction to low index of refraction, bend away from the normal. n2< n1 and theta 2 > theta 1.
vertical velocity determines the time of flight
if two projectile leave the earth with the same vertical velocity, they will land at the same time regardless of their horizontal velocity.
does mass affect projectile motion?
NO mass does not affect projectile motion assuming there is no air resistance.
when presented with force, think accerlation and when presented with acceleration, think force
force = mass* acceleration
what are the 4 types of forces?
- strong nuclear force
- weak nuclear force
- gravitational force
- electromagnetic force
if something is rotational equilibrium, does it have a torque?
NO it does not have a torque.
all machines ( ideal or nonideal ) decrease the amount of force is done on the machine BUT
If it is an ideal machine, the amount of work is conserved therefore the same,
If it is an non-ideal machine, the amount of work is not conserved therefore it would require more.
dymanic equilibrium
no accerlation, velocity is nonzero
static equilibrium
no accerlation and velocity is zero.
If a brick is floating on top of the sterofoam, the volume of water is displaced will be equilvalent to the mass of the brick. because the brick is much heavier/more dense , more water will be displaced .
Yet if the brick sinks, only the volume of the brick will displace the water therefore the water level will decrease once the sterofoam is removed.
If a brick is floating on top of the sterofoam, the volume of water is displaced will be equilvalent to the mass of the brick. because the brick is much heavier/more dense , more water will be displaced .
Yet if the brick sinks, only the volume of the brick will displace the water therefore the water level will decrease once the sterofoam is removed.
in an ideal fluid, velocity through a cross section is contstant
in a real fluid, the velocity through the cross section varies, fastest trhough the center and slower towards teh edges
Resistance is directly proportional to L
Increase L leads to Increase in resistance. and indirectly proprotional to r^4.
increase in radius –> decrease in resistance.
V=IR analagous
Delta P = QR
Delta P = change in pressure
Q= flow
R=resistance
Capillary action - water being puled upward there defying gravity
The intermoleculr forces betwen water molecules are weaker than the intermolecular forces between water and soil
Surface tension - intensity of the intermolecular forces fluid per unit length
a water droplet with stronger intermolecular forces have a greater surface tension which will cause it to bead up more
intermolecular forces pull inward
in an aneurysm, greater radius wil result in a decrease in velocity due to the continuity equation.
but due to energy conservation, a decrease in dynamic pressure results in an increase in static pressure.
this is why they say, aneuysms can BLOW up.
in an aneurysm, greater radius wil result in a decrease in velocity due to the continuity equation.
but due to energy conservation, a decrease in dynamic pressure results in an increase in static pressure.
this is why they say, aneuysms can BLOW up.
if voltage is negative, current is moving towards the cell and the electron is moving away from the cell.
if a voltage is positive. the current moves away from the cell and the electrons move toward the cell.
if voltage is negative, current is moving towards the cell and the electron is moving away from the cell.
if a voltage is positive. the current moves away from the cell and the electrons `move toward the cell.
index of refraction
when you have the lowest index of refraction = fastest speed of light
n=c/v
c=speed of light in vacuum
v=speed of light in medium of interest.
in a capillary, as you decrease the denisty value, you increase the height.
if you change the fluid from mercury whose density is 13 to water whose denisty is 1, the height will be increased by 13x.
Capacitor Energy equation
U= 1/2 CV^2
Increasing the voltage across the plate will increase the Charge on the capacitor but it wil not change the properties of the Capacitance
C=EoA/d
only if you change the above variables can you change the capacitance
Visible light has a Frequency in what range?
10^15 Hz
if you increase frequency, you decrease wavelength
Specific gravity = ( density of object)/(Density of water)
if the specfic gravity = 0.98 what percentage is under water?
98% will be submerged under water
Snell law
n1sin(Theta1)=n2sin(theta2)
n=c/v
for visible light, greater frequency = lower wavelength, and the more it refracts
when shining a light trough a prism causing dispersion, the red light will bend the LEAST and the Violet will bend the most
( ROYGBIV)
Power = energy/ time
P=I^2R = V^2/R =
To prevent loss of power when transferring from the power house to your home, it is transported on HIGH voltage lines and therefore the current will be decreased
Capacitor in series
1/Ceq = 1/c1+1/C2 + 1/C3
Capactor in parallel
Ceq = C1 + C2 + C3
resistor in parallel
1/Req= 1/R1 + 1/R2 + 1/R3
Resistor in series
Req= R1 + R2 + R3
Resistor in series
Req= R1 + R2 + R3
According to Archimedes principle, Ratio of density of an object to desnity of fluid submerged = weight of the object in air to the difference of the weight in air - weight under water
P obj/P fluid = ( weight in air )/ ( weight in air - weight in water )
damping ( attentuating()
= loss of energy at the resonance freq
which means there is a loss in intensity
frequency is determined by the source –> therefore it can not change.
as intensity decreases, amptitude decreases and wave velocity decreases.
damping ( attentuating()
= loss of energy at the resonance freq
which means there is a loss in intensity
frequency is determined by the source –> therefore it can not change.
as intensity decreases, amptitude decreases and wave velocity decreases.
sounds travels the fastest in solid > liq>air
it stil needs a medium to propagate therefore sound can not be heard in vacuum - where the density = 0
open and closed Pipes equation
open : f= ( nv)/2L ) where n = 1,2,3,4
Trick! cound the number of antinode to figure out which harmonic
n=1 fundamental freq
n=2 = 2nd harmonic ( 1st overtone) etc
closed: f=nv/4L where n = 1,3,5 ( count the number of node to determine harnomic )
n= 1 fundamental freq
n=3 3rd harmonic ( 1st over tone (
open and closed Pipes equation
open : f= ( nv)/2L ) where n = 1,2,3,4
Trick! cound the number of antinode to figure out which harmonic
n=1 fundamental freq
n=2 = 2nd harmonic ( 1st overtone) etc
closed: f=nv/4L where n = 1,3,5 ( count the number of node to determine harnomic )
n= 1 fundamental freq
n=3 3rd harmonic ( 1st over tone)
the ear canal is a tube with one side open and the other side closed. therefore the f=nv/4L
shorter canal = increased freq. this explains why dogs can hear higher freq.
the ear canal is a tube with one side open and the other side closed. therefore the f=nv/4L
shorter canal = increased freq. this explains why dogs can hear higher freq.
ears are far apart enough that sound will reach one ear before it reaches the other ear. We use this to determine which direction the sound came from.
Although it is true that the intensity wil decrease with increasing distance, the ears are not so far apart that the intensities will be different.
HUman ear can determine time difference better than intensity difference!
ears are far apart enough that sound will reach one ear before it reaches the other ear. We use this to determine which direction the sound came from.
Although it is true that the intensity wil decrease with increasing distance, the ears are not so far apart that the intensities will be different.
HUman ear can determine time difference better than intensity difference!
in an echo, there should be 2 x distance = 2 times the time because the time to hit the object and the time to bring it back.
if object is approaching the detector, the time will decrease.
if the object is moving away from the detector, the time will increase.
in an echo, there should be 2 x distance = 2 times the time because the time to hit the object and the time to bring it back.
if object is approaching the detector, the time will decrease.
if the object is moving away from the detector, the time will increase.
Intensity ( I) is proportional to 1/r^2
only if the intensity decreases by a factor of 1/10 will the dB change by 10. if not, it will be less than 10 dB
Intensity ( I) is proportional to 1/r^2
only if the intensity decreases by a factor of 1/10 will the dB change by 10. if not, it will be less than 10 dB
highest reflected frequnency results from the largest doppler shift.
the doppler shift is the greatest when the objects are moving toward one another at the highest possible speed.
highest reflected frequnency results from the largest doppler shift.
the doppler shift is the greatest when the objects are moving toward one another at the highest possible speed.
an increase in the index of refraction of a lens would increase the bending of the light rays, which would increase the power of the lens
. An increase in the index of refraction of a lens would increase the bending of the light rays, which would increase the power of the lens.
When light travels from one medium to another, light bends. if n is similar, light bends less and therefore it will decrease in magnifying.
this is why there is a large magnification between air( n= 1) to glass n=1.5 rather than under water n=1.3 and glass n=1.5
in order to increase power , increase the current
p=IV = V^2/R = I^2 R
in order to increase power , increase the current
p=IV = V^2/R = I^2 R
Atomic weight
the number of ptorons - which determine the chemical properties of the element
Mass number define
number of protons + neutrons
Atomic weight =
average of the all isotopes.
1 period = define
`time it takes to reach one full wavelength
as you approach source, increase freqiency and as you move away from the sourcec, you decrease frequency
think about James’ analogy to tennis balls. as you run towards the ball spitter, you will be hit by them more frequently, freq increases and vice versa is true as you run away from the tennis ball spitter.
as you approach source, increase freqiency and as you move away from the sourcec, you decrease frequency
think about James’ analogy to tennis balls. as you run towards the ball spitter, you will be hit by them more frequently, freq increases and vice versa is true as you run away from the tennis ball spitter.
