Sunday, November 29, 2009

Phy Science - Weather Review

Check this link to review cloud types. Remember fog is really a ground level cloud.

Middle-latitude cyclone/wave-these are the weather producers in the United States. Every storm system we looked at in Michigan has been associated with these weather producing systems. 

Processes that lift air- be sure to also look at your notes
  • orographic lifting- air rising/dropping over mountains
  • localized convective lifting- clouds forming on warm summer days
  • convergence- Florida peninsula
  • frontal wedging- warm air forced up over colder air

Phy Science - Weather Review

Water Vapor - water vapor is the gas that that drives atmospheric processes. When water vapor condenses around dust, smoke, salt particles (condensation nuclei) clouds can form along with precipitation- rain, snow, sleet hail, etc.
Phase Changes- water can undergo phase changes at the Earth's surface.
  • melting- solid to liquid,
  • evaporation - liquid to gas
  • condensation- gas to liquid
  • freezing- liquid to solid
  • latent energy- the energy that is stored in water, see notes.
Relative humidity- indicates how close the air is to saturation. Warm air can hold more water vapor than cold air. Check notes.
Dew Point- the temperature at which the air needs to be cooled to reach saturation/ clouds can form.
Adiabatic- the cooling/heating of air due to a change in pressure. When air is compresses (higher pressure) it  will warm. When air expands (lower pressure) it will cool.
Wet adiabatic rate-is less than the dry adiabatic rate because of latent heat.

Sunday, November 15, 2009

Phy Science- Temperature Controls


Prevailing Winds.
In the continental United States the prevailing direction of the wind is from west to east. Cities on the west coast/windward side of the continent will have their temperatures moderated by the wind coming off the Pacific Ocean and will have cooler summers and milder winters. Cities on the east coast/leeward side are not influenced as strongly by the Atlantic Ocean as the prevailing wind is blowing offshore.

Below is a map showing lines that connect equal temperatures in the United Sates. These lines of equal temperature are known as isotherms.


Cloud cover also acts as a temperature control. On a cloudy night the clouds act like a blanket absorbing outgoing radiation from the surface of the Earth. The clouds help keep the air temperature higher than on a clear night.

Phy Science- Tepmerature Controls


When looking at the Earth notice that the southern hemisphere is covered with much more water than the northern hemisphere. Due to this large difference in the area covered by water the annual temperature ranges in the southern hemisphere are generally smaller than those in the northern hemisphere. It is interesting to note that cities at the same latitude north and south of the equator, at the same altitude, the southern city will have a smaller temperature range.

Phy Science- Temperature Controls



Temperature controls on Earth are influenced by three factors: altitude, location and heat capacity. If you have had the opportunity to visit the Rocky Mountains in the summer you may see snow on the tops of mountains. This is due to the fact that temperature decreases with altitude. We have discussed in class that water takes a long time to heat up and a long time to cool down, whereas the land heats up and cools down quickly. This ability to absorb heat by an object is referred to as heat capacity. Omaha Nebraska (top graph) is located in the interior of the United States not near a large body of water. Omaha will have extremes in temperatures during the year due to the fact that the land will not retain its heat. The graph below of London, near the ocean will have smaller temperature ranges because of the moderating influence of the ocean. We see this effect in Michigan with temperatures on the Lake Michigan shoreline versus those cities inland.


Phy Science - Transfer of Heat

Heat can be thought of as the motion of particles within a substance. This energy of motion is known as kinetic energy. Heat, energy, always moves from areas of high concentration to areas of low concentration (differences in temperature). The troposphere is heated from the ground up by the re-emitting of solar energy. This heat emitted from the ground is absorbed by gases in the troposphere known as the greenhouse effect.


Energy (heat) is transmitted by three processes:
  • radiation- energy from the sun reaches the Earth through this method.
  • convection - the transfer of heat by the movement of mass in a fluid (water or air).
  • conduction- transfer of heat by molecular movement- one molecule hitting another.


Phy Science - Atmosphere


The Earth's atmosphere is a mixture of gases. The most abundant gas in the atmosphere is nitrogen 78% with oxygen the 2nd most abundant at 28%.

Troposphere- (lowest layer) this is where we live and weather occurs, temperature decreases.
Stratosphere- temperature increases, this layer contains the ozone layer. Ozone is three atoms of oxygen combined and the ozone protects from UV radiation.
Mesosphere- temperature decreases, meteors burn up in this layer.
Thermosphere- temperature increases, beginning of outerspace.

Pauses- these are the boundaries between layers of the atmosphere, see diagram.

Sunday, November 1, 2009

Mid-Term Review


  • centripetal acceleration- is towards the center of the curve
  • acceleration of gravity - is constant
  • gravity caused the formation of the Sun and the planets from a nebula
  • speed=distance/time
  • KE=1/2mv2
  • GPE= mgh
  • terrestrial planets have a solid iron core due their closeness to the Sun (gravity)
  • review phases of the moon material

Mid- Term Review


  • elliptical orbits- to calculate, eccentricty= distance between foci/length of major axis
  • transverse wave- particles move perpendicular to the direction of travel
  • compressional wave- particles move parallel to the direction of travel
  • refraction- the bending of light as it moves from one substance to another
  • diffraction- the bending of a wave around an object
  • EM waves- have an electric and magnetic field
  • distance- how far the route is you take to get some somewhere
  • displacement- how far one travels as "the crow flies"

Mid Tem Review


  • Remember seasons are caused by the Earth's tilt NOT how far the Earth is from the Sun. In the diagram the first day of winter in the northern hemisphere would be on the far left- northern hemisphere is tilted away from the Sun.
  • Blue shift/red shift- red shift is evidence of an expanding universe where a blue shift would indicate a contracting universe.
  • eclipses- review diagrams, lunar eclipse ( Sun-Earth-Moon), solar eclipse (Sun-Moon-Earth).
  • review contour maps
  • amplitude- for a light wave this is brightness, for sound loudness
  • wave speed= frequency X wavelength
  • Doppler effect/shift
  • mass- does not depend on gravity, mass is a property of the object
  • weight- depends on distance from the center of gravity

Tuesday, October 20, 2009

Black Holes and the Big Bang Theory





















Black holes (picture on left) - are theorized to form when a massive star collapses at the end of its life. Centers of galaxies contain black holes. The gravitational field of a black hole is so great that not even light can escape from a black hole.

Big Bang Theory- the theory that proposes the Universe originated from a state of high temperature and density. This theory says the Universe began about 13.75 billion years ago. One piece of evidence of the Big Bang theory is the existence of cosmic background radiation (top picture). This radiation, from all directions in the sky, is said to be left over from the big bang.

Milky Way Galaxy





















The Milky Way is the galaxy which contains our Sun. Our Sun is located within one of the spiral arms. Our galaxy is a collection of stars and interstellar dust. This dust/matter known as a nebula is the birthplace of stars. gravity is the force which pulls this matter together.
The average distance between stars in our part of the galaxy is 5 light-years. A light-year measures distances between interstellar objects (the distance light travels in one year).

Lenses


The two basic types of lens are pictured to the left. Top lens is a convex ( converging lens). Bottom lens is a concave (diverging lens).


Convex lens- magnifies, enlarges, image is inverted.




Concave lens- diverging, spreads light apart, image is reduced.

Diffraction


Diffraction- the slight bending of a wave around the edge of an obstacle in its path.

H-R Diagram
















The Hertzsprung-Russell (H-R) diagram shows the relationship between temperature and absolute magnitude.

  • 90% of all stars are main sequence stars
  • blue stars have the highest surface temperatures
  • the brightest main-sequence stars are also the hottest.
  • the Sun is an average main sequence star, yellow in color
  • as our Sun ages it will eventually become a red giant
  • the Sun has an absolute magnitude of +5

Our Sun









Our Sun and solar system was formed from a huge cloud of dust and gases that condensed due to the force of gravity.
Scientists by studying the Sun's or any star's spectrum can determine the chemical composition of that star. Our Sun is composed of 71% hydrogen, 27% helium and 2% heavier elements.

The Sun's energy is produced by nuclear fusion. This process combines, fuses, hydrogen atoms into helium atoms. Some mass is lost during this process and transformed into energy. This energy is radiated into space as the EM spectrum and the solar wind.

The solar wind is a stream of electrons and protons which are emitted from the Sun's corona. The corona is the outer gas layer of the Sun seen during solar eclipses.

The Sun is a large nuclear fusion reactor that has enough fuel, hydrogen, to burn for approximately another 5.5 billion years. Our Sun like all stars will eventually run out of fuel, hydrogen, and collapse.

Doppler Effect Sound and Light

www.exploratorium.edu/origins/hubble/tools/doppler.html

Check this link about the Doppler effect.

Sound Waves


Sound Waves:
  • sound needs a medium to travel through
  • the sound wave is a compressional wave
  • the particles of the wave are compressed, then released, thing of a Slinky





Bats use ultrasound (above human hearing) to locate food sources- bugs. This process is known as echolocation.












Sonar- the process of reflecting sound waves underwater to locate objects.

Sunday, October 18, 2009

Concave Mirrors & Light


Concave mirrors- like the bowl of a spoon. The image formed is enlarged and upright.









We can see object because light is being reflected from those objects. The color of the object depends on the frequency of light being reflected. White light ( which contains all colors, think prism) when striking an object will absorb some of the colors, while reflecting back others- we see reflected light.

Refraction of light- as light travels from one medium to another it will change speeds, object appears to be bent.

Mirrors

Mirror- any smooth object that reflects light to form an image.

Plane mirror
  • angle of incidence = angle of reflection
  • image is virtual
  • image is "behind" the mirror the same distance as it is in front of the mirror.












Convex mirror- light rays diverge (spread apart) greater field of view. Automobile outside mirrors are convex mirrors.

Physical Science Waves


Electromagnetic Waves- electric and magnetic field that are perpendicular to each other.

  • transverse waves
  • do not need a medium
  • light is a EM wave
  • light is a combination of a wave and particle
  • photon- packet of energy/ particle that carries energy.
  • waves will travel as long as there is energy to carry
wave speed = frequency x wavelength
  • wave speed (ws) is measured in m/s
  • frequency (f) is measured in hertz
  • wavelength is measured in meters
  • the speed of a light wave is a constant in a vacuum (symbol "c") is 300.000 km/s
  • speed of a EM wave will decrease as it enters a more dense medium
  • the higher frequency EM waves will have short wavelengths, low frequency will have longer wavelengths.
  • gamma rays have the the shortest wavelength/ highest frequency.
  • EM spectrum ( low frequency to high)- radio, infrared, visible, x-ray, gamma.

Tuesday, October 13, 2009

Chem Chap 3 Review

Standard Metric Units

  • mass- kilogram, kg
  • volume- liter, L
  • length- meter, m
  • time- second, s
  • temperature - Kelvin, K- neat thing about Kelvins no negative values, cannot get colder than absolute zero.
Weight- is the pull of gravity on an objects mass, therefore weight is dependent on gravity. Another way to look at this is an objects position, location, from a source of gravity. Farther away from gravity object will weigh less.

Density- is an intensive property of the object, that is it does not depend on the "amount" of the object. D=mass/volume. Be sure you can calculate for any variable in the density formula. Refer back to your worksheet for problems.

Factor-Label Method- be sure to review this. 100cm= 1m, therefore it also can be written:
1m/100cm or 100cm/1m.

Scientific notation
  • when moving decimal to the right- negative exponent
  • when moving decimal to the left- positive exponent
  • after moving decimal only one number to the left of the decimal point.
  • when multiplying add exponents, dividing subtract
ex: 0.0000045 4.5 x10 -6
450000 4.5 x10 5 ( -6 and 5 are exponents)
3 x 10 3 X 4 x 10 -6 12 x 10 3 +(-6) 12 x 10 -3 1.2 x 10 -2
8 x 10 4 / 2 x 10 -5 4 x 10 4 - (-5) 4 x 10 9

Significant Figures

Refer to rules in your notebook. In multiplication and division your answer can only have as many sig figs as the least precise number ( lowest number of sig figs)

ex. 0.001 1 SF
0.00100 3 SF
0.001001 4 SF
100 1 SF
101 3 SF
101.0 4 SF

Sunday, October 4, 2009

Physical Science Review

For the test Friday be sure to review:
  • your packet on Topographic Maps.
  • diagrams of solar and lunar eclipses
  • how to calculate speed
  • scientific notation
  • factor-label conversions
  • metric relationships
  • Newton's Laws of Motion
  • difference between mass and weight
  • rotation- spinning on axis, causes night and day
  • revolution- orbit around the Sun
  • cause of the seasons- tilt of the Earth on its axis
Famous astronomers:
  • Ptolemy- proposed the geocentric model of the universe
  • Copernicus- given credit for the heliocentric model of the solar system
  • Galileo- inventor of telescope
  • Kepler- discover elliptical shape of planetary orbits.
  • Newton- discovered forces that keep planets in orbits
Moon Info
  • period of rotation and revolution are the same- 27 1/3 days
  • moon has no atmosphere therefore, no weathering, craters are present
  • age of moon is the same age as the Earth
  • waxing- new to full moon
  • waning- full to new moon
  • takes the moon about 4 weeks to go through a full cycle

Monday, September 21, 2009

Chemistry Test Review

Chemistry is the study of the composition and structure of matter. Chemistry studies the changes of matter- one can use the scientific method to study these changes in matter.
Energy changes are NOT changes in matter.
After observing a series of experiments a chemist can develop a THEORY to explain these observations.

Matter has two general types of properties:
1. extensive- "how much" such as mass and volume
2. intensive- does not depend on how much such as density.

Physical properties include- melting point, hardness, color, evaporation .
Chemical properties depend on how the substance combines with other substances: rusting, combining with oxygen.

States of Matter

Solid- definite shape and volume
Liquid- definite volume, takes the shape of its container/ indefinite shape.
Gas- indefinite volume, fills its container, easy to compress, expands when heated.
Vapor- gas phase of a substance that typically a solid or gas at room temperature.

Mixture- a blend of substances which are "easily separated".
Homogeneous mixture- same throughout, not chemically combined, "stainless steel".
Heterogeneous mixture- not the same throughout, soil, Italian salad dressing.

Chemical compound- substances that are chemically combined, can only be separated by chemical means.

During a chemical reaction matter is NOT created or destroyed, only changed.

Wednesday, September 16, 2009

Physical Science Wed Stuff

Density is an intensive (does not depend on amount) property of the object.

Density = mass/volume, typically units are g/ml

Algebra
The old standby "Cross Multiply and Divide". This can be used when you have two ratios equal to each other.

a/b=c/d

Step 1- Cross multiply numerator on the left side x denominator on the right. In our example (ad)

Cross multiply denominator on the left side x numerator on the right. In our example (bc)


So we get ad=bc

Let's solve for the four variables.

Step 2 - Divide,

Solving for a ad/d= bc/d ------> a= bc/d

Solve for d ad/a= bc/a -------> d= bc/a

Solve for b ad/c = bc/c -------> ad/c = b

Solve for c ad/b = bc/b --------> ad/b = c

Tuesday, September 15, 2009

Sunday, September 13, 2009

Chem and Phy Sci- Graphing

Lee Marek
1. Use graph paper (home-made graph paper is unacceptable) ink or pencil. Better yet do it on Excel, other spread sheet programs or some graphing program.

2. Plan ahead! Note the largest value number to be plotted on each axis and make sure your scale is large enough so that you use up at least half of the paper in both directions.

3. Label the axis and give units to those labels in parenthesis: LABEL (UNITS) as in distance (cm).

4. All graphs should have a title. A good title that always works is "y" as a function of "x" as in (A). The independent variable is usually plotted on the horizontal (x) axis. "Distance as a Function of Time" is a good title for graph (B).

5. Most graphs should start at the origin (x = 0, y = 0). There are exceptions like graphing temp. If your lowest temp. is 51o C start at 50o C. This is because 0o C has no special meaning (0 cm means no distance, 0o C doesn't mean no temperature).

6. Pick a logical scale, counting by .1, 1, 2, 5, or 10 etc., not 3, 5, 7, 9, etc.

7. Put a small circle around each data point lightly in pencil. This is necessary due to the uncertainty in the data. Excel will do this for you.

8. Look at your points. Draw the best straight line or smooth curve that goes through as many points as possible. Point to point connections are usually not used in science but are quite valid for plotting irregular data which does NOT display any regularity - like gold prices. Try to miss as many points above the line as you draw as below. Excel will do this for you, as will many graphing programs.

9. If 2 or more lines are plotted on a graph a key is needed. It should be placed on the right side and toward the top if possible. A different color ink must be used for each line. Again Excel will do this for you.

10. If you have a straight line though the origin you have a direct proportion (A). When one variable goes gets larger so does the other. In graph (B) you have an inverse relationship. When one value becomes larger (say pressure) the other (volume) gets smaller.

Here is a quick check list:

TITLE, KEY (if needed), LABELS + UNITS, BIG ENOUGH, LIGHT CIRCLES AROUND POINTS, SMOOTH LINES/CURVES

Monday, May 18, 2009

Ocean Cross-section







  • Continental shelf- the continuation of the continent into the ocean.
  • slope- the abrupt drop-off from the continental shelf.
  • rise- the accumulation of material falling off the slope.
  • abyssal plain- the deepest part of the ocean. The oldest and densest basaltic rock.
  • mid-ocean ridge- divergent boundary, magma flows onto the ocean floor here creating new crust.

Sunday, February 8, 2009

Ring Around the Moon


Picture credit: Chris Sprik

This ring around the moon is produced by the moonlight being reflected through 6-sided ice crystals in a thin uniform layer of cirrus clouds.

Beautiful blue skies today- remember that clear skies are produced by a high pressure system (clockwise rotation, sinking air). Amazing how fast the snow melts when there is an increase in the air's kinetic energy- ie: warmer weather.

Saturday, January 10, 2009

Sunshine On My Shoulder



Insolation- is the amount of the sun's energy that reaches a point on the earth's surface. This energy varies based upon the time of year and the latitude. For example for us, northern hemisphere, during the winter we receive less energy because we are tilted away from the sun. In fact the North Pole gets no direct sunshine during the winter.





Let's look at this skew-T diagram: this diagram shows the relationship of atmospheric temp (solid line) to dewpoint temp (dotted line). Few things to take note-dew point is always to the left of temp, as air moves up in the atmosphere its temperature decreases and moves away from the dewpoint. Also, when temperature and dewpoint are close together the air's relative humidity is high, clouds can form and precipitation can also occur.