this is part one of the two-part review for the earth science New York State Regents course by Regents main simpler my name is Donnie rudansky I will go through this review now on the earth science region they give you a reference table 16 pages and it's very important to be familiar and know all the different pages because a lot of the questions are based on the reference table so as I go through the review I'll go through the different pages of the reference table to help you understand the material on page one of the reference table you are given these equations there are four equations eccentricity the gradient the rate of change and density so first we'll talk about these two equations that are given the rate of change and the density so first you have the rate of change the rate of change is the change in value over time so for instance a question they may ask they'll give you this data table and they'll say calculate the rate of change in the inside air temperature from 8: a.m. to 2 p.m. and C Celsius degrees per hour that's the change in value over the time so in this case it's from 800 p.m. to 2 p.m. so the change in value is going to be from 24 to 15 so from 24 to 15 is going to be 9 so that's 9 degrees is the change in value over the time it's 2 p.m. to 88 a.m. 2 p.m. minus 8 a.m. the number of hours between that is going to be 6 hours so the rate of change is a change in value over the time which in this case is 9 degrees Celsius per over 6 hours so therefore 9 divided 6 is going to be 1.5 that's a rate of change from those two points is 1.5 Celsius per hour that is the rate of change that to know for the region you then also have an equation called density now density what density is you have density equals to mass over volume so first you have volume volume is the measure of space how much there is in a certain space it's usually me measured in cubic meters which is 3D and that is volume now inside that volume you have mass now everything is made up of atoms which make up into compounds and that makes up matter so mass is the matter basically the number of compounds in a specific space that's called mass and that's usually measured in grams for G so density is the mass over the volume this would be low density that would be high density right low density and here is high density you have more atoms more compounds in that given space so there's more mass and that's higher density now an example here if you have 22 gram of mass mass in 5 Cub cenm of volume it's the mass over the volume is equal to the density density density tells you how much mass there is per one ubic one unit of let's say cubic centimet of volume so for instance if this was 22 gr it would be 22 G which would be the mass over the volume which is 5 cubic cenm so 22 ID 5 is going to give you 4.4 that's 4.4 G per cubic centimeter and that would be the density the mass per one unit of volume would be the answer here's another example you have 7 G and 3 Cub CM it would be 7 ID 3 which will give you 2.3 3 G per Cub CM back all the way to the very beginning of the start of our existence the universe 14 billion years ago we have an event called the big bing that is what started it all the first you don't have anything there's nothing we don't know exactly what this means but what popped into existence was this very small dot of energy smaller than the top the tip of a pin of a needle and that small energy then expanded and exploded into all directions and that is called the Big Bang the Big Bang happened 14 billion years ago that small that expanded and exploded into all directions that energy then cooled down to form the early atoms the hydrogen atoms those were the first atoms the atoms make up the physical Universe they made up a proton neutron and an electron and those were the first things in the universe the hydrogen atoms these hydrogen atoms will then get pulled together by gravity gravity what gravity is gravity is a force is that the universe is basically like a giant fabric anything you put on that fabric will cause the Universe the the fabric of the universe to bend so the bigger the thing is The more mass there is the more the gravity that it will have the smaller it is the less gravity it will have so the more massive and closer objects are equals to the stronger the gravity is going to be it's like a giant trampoline if you stand if you are very heavy and you stand on trampoline it's going to pull the trampoline a lot anything around it will be attracted to it very much that is what gravity so gravity is a major force in the universe and that gravity will help to pull these hydrogen atoms together the hydrogen atoms come come together and the force of gravity the more and more will create this very very high pressure and high temperature area in the center of this cluster of hydrogen atoms and that cluster they will start to collide together by a process called nuclear fusion nuclear fusion is the hydrogen atoms inside that there's so much pressure and so much temperature they will start to collide with each other and releasing a tremendous amount of energy and that energy will help to form the Stars so stars are formed by nuclear fusion and that is how Stars continue to emit all their light and all their radiation is by the process of nuclear fusion that is nuclear fusion now these Stars will get now get pulled together by gravity to make galaxies so galaxies are these clusters of billions and billions of stars you have the galaxies are based on their shape they are identified based on their shape so you have spiral it looks like a spiral galaxy so this is called spiral this is called irregular because there's no shape And this is elliptical galaxy because it's shaped like a circle basically so it's based on their shape now the different galaxies are all together and that is called the universe the universe contains all of the galaxies inside of it um the universe again that began around 14 billion years ago now how do we know that the Big Bang occurred 14 billion years ago there are two proofs that you have to know for how the Big Bang occurred the first is cosmic background radiation is that in the in the background of the universe there is a lot of radiation so if you go let's say to Japan and you go to Hiroshima Nagasaki you'll see a lot of radiation in the air because a atom bomb was dropped there uh 60 years ago so same thing with the universe is that there was a humongous explosion so there's still some of that radiation in the background of the universe so that is a proof for the big bing a second is called the Doppler effect now the Doppler effect is that on if you if on page 14 of the reference table you have the electromagnetic spectrum and based on the different wavelengths you will see different colors of light if it's a short wavelength you see here decreasing wavelength so the wave is very short you'll see blue or Violet that's why you see the different colors if it's a longer wavelength you'll see it as red or orange so the Doppler effect is that when scientists look out into the uh into other galaxies they see all these Galaxies have this red shift because these galaxies as you see here the galaxies are moving away from us they have this red shift they must be moving away causing the wavelength to get longer so they see them as red they're therefore inferring that the Galaxy must be moving away from us at incredibly high speeds to cause the wavelength to expand a lot and therefore we now see it as red if it was going towards us we would see it as blue but most of the Galaxies have this red shift so therefore it's inferring that they must be being being expanding away therefore the universe must be expanding from a single point and approved to the big bing by nuclear fusion so you have the stars are formed because you have again the mass of the hydrogen atoms the more hydrogen atoms you have the bigger the star will be the more massive the star will be and you can see here the Stars diagram you could have a average star or massive star again based on how much hydrogen atoms there are how much how much of that gas formed into the nuclear fusion to form these Stars they could grow in size by having more hydrogen atoms and then they could eventually explode into a supernova or into nebula and then they become a white dwarf which would be the final stages of a star or a neutron star or become a black hole that is this the the life of a star so you have the characteristics of stars on page 15 of the reference table so here's the characteristics of stars so we have you have many different Stars not all the stars but some stars in our galaxy so you have on the left side is Luminosity which is the rate at which a star emits energy relative to the Sun so relative to the Sun how much energy they emit how bright that star is going to be the sun is at one so therefore the other stars here uh the sun is at that's where we're look at that's at one and the other stars are based on that so you see series is about 10 times more luminous is 10 times more brighter than the sun speaka is like almost 10,000 uh as bright as the sun the surface temperature is how hot that star is on the surface so it's relative so these are relatively low temperature on the surface and these are much higher so speaka they have a higher temperature uh battal goes have a lower surface temperature these are small stars to massive stars so small as on the bottom and then these stars are much more massive they are much bigger than the other stars on the bottom you also have the color so you have Spa is blue again it's High Luminosity it's high it's a big star and also it is high temperature these are red Bal goose is a big star but it's low surface temperature and high in luminosity and it is a surface temperature of red now you also have the different stages of the Stars first they start in the main sequence here is the early stage it says and then again if the star gets more hydrogen atoms it could grow in size and become a giant star or a super giant star but then like we saw before it could explode and become a white dwar which is a late stage star so now the Sun is right here and the Sun that is our star we are located around the sun the sun is a mean sequence star and the Sun is located in the Milky Way galaxy like these other stars as well again a galaxy is a collection of billions of stars so the sun is within the Milky Way galaxy and the sun makes up our solar system the sun is referred to as the solar so it makes up a solar system and this formed about 4.6 billion years ago again the Big Bang was 14 around 14 billion and then around 4.6 billion years ago the solar system formed the sun formed and then because of gravity the other planets will now orbit around the Sun so on page eight of the reference table it actually tells you the GE geologic history and over here you can see 4.6 billion is the estimated time of origin of Earth in the solar system now these These are called planets planets are these celestial bodies that orbit around the Stars so we are we are on a planet called Earth and in our Solar Sy system we have eight of these planets now these planets they uh is called the heliocentric model Helio refers to the Sun and that is called the Sun at the center so heliocentric that is as opposed to the geocentric model which was that they used to think that the Earth was at the center but really the sun is at the center so it's called heliocentric and the planets they orbit around the sun they don't orbit in a circle they orbit in an elliptical orbit which means that it's slightly oval called an elliptical orbit and we have eight planets in our solar system you have the first four Mercury Venus Earth and Mars these are referred to as terrestrial planets these are called terrestrial they are small in Mass they are smaller and they are higher density which means that you could stand on them so these are called terrestrial the the other four the outer four are called Jovian these are much bigger planets Jupiter Saturn Uranus and Neptune they are much bigger and they are low density they are gashes you can't actually stand on Jupiter you would fall through it is this heavy gas now in between the terrestrial in the Jovian you have this belt called the asteroid belt the asteroid belt is a belt of a lot of rocks which orbit around the Sun that is called the asteroid belt in between Mars and Jupiter these asteroid belts sometimes Collide into planets for instance our moon it collides into it and it creates these hold called craters so also the formation of the planets what you should know is that the gravity caus more dense materials to be pulled towards the center causing the planets to be become layered that the more denser materials move more to the center causing the planets to be layered which we'll discuss later on in part two in the reference table you have the different data about our solar system again you have the four first planets are called Mercury Venus Earth and Mars as a terrestrial and the other four are called Jian so you have the different data about these planets so first you have the mean distance from the Sun that means how far away they are from our sun which is our the star closest to us so that's the mean distance from the Sun you can see how Mercury is the closest and you have nept is the furthest away from the Sun you then have the period of revolution which means how long it takes a planet to make one full circle around the Sun that is called the period of revolution D is in days and Y is in years so it takes Mercury 88 days to make one full orbit one full revolution around the Sun it takes earth 365 days that is how many days there are in a year so that's how long it takes Earth to make one full orbit one full revolution around the Sun if you do 365 divided by 360 Degrees which are in a circle that would be one degree per day so the Earth's rate of revolution is going to be it is moving at one degree per day now the period of rotation rotation is how long it takes the planet to make one full spin on its axis that is called rotation so Revolution is moving around the Sun in an orbit rotation is how long it takes the planet to move to spin on its axis if you see the Earth here the Earth takes 20 about 24 hours to make one full orbit which one for rotation one full rotation around its axis if you did 360° that's how many degrees there are in a circle divided by 24 you would get 15° therefore the Earth is rotating at a rate of 15 degrees per hour so it's 1 degree per day for Revolution and 15 degrees per hour for the rate of rotation now the acentricity of the orbit again the planets do not have a circular orbit around the sun they have an Ecentric orbit around the Sun acentricity is how ovular the orbit is zero would be a circle and one would mean that it's a straight line so if you see the planets here they are close to zero they're not at zero which would be a complete circle they are they are like 017 093 mercury has the greatest eccentricity which means that it's the most ovular in its orbit around the Sun so the equation for that is on page one of the reference table and you have to know it for the practicals the eccentricity is equal to the distance between the folky over the length of the major axis I'm not going to get into it so much now but it's for the practicals but this would be zero and then this would be let's say 0.02 now the folky folky at two points that are equidistant to the center of the orbit so here is the center of the orbit so the folky is two points that are equidistant to the center the sun is at one of the folai so here's the Sun at one of the folai and here is another imaginary point that is equidistant uh with the sun to a point that is in the center of the orbit so you take the distance between the folky and you divide it over the length of the major axis which is from theow longest points in the orbit and that would give you the eccentricity of that planet this would be a longer Planet a longer eccentricity so the more Ecentric the planet's orbit is the more distance there will be between the planet's FY now also a planet that is closer the closer the planet is to the Sun the more gravity that there's going to be the more gravitational attraction that there's going to be like we said before the closer the planets are the closer two objects are the more gravitational pole they'll be therefore the planet will go the fastest at that point so the planet will move the fastest in its orbit when it's closest to the Sun it'll move slowest when it's away from the Sun the furthest away so the closest to the Sun equals the the greater the gravity and the faster the orbit therefore we have the equatorial diameter which is how big it is at its diameter and if you see here the terrestrial planets they are much smaller in mass than the Jovian Planets the Jovian planets are much larger inass Mass you see a much much bigger equatorial diameter which means how big it is at at its largest point and you have the mass these are smaller and mass terrestrial planets compared to the Jovian planets which are much more massive you see how they have a much bigger number when compared to the terrestrial planets however the terrestrial planets they are much higher in density they are high density they are therefore Rocky higher density therefore you could stand on these planets you could stand on Earth you could stand on Mars but the Jovian Planets you see they have a much lower density of 1 3 1.8 which causes them to be this heavy gas so they're called gas giants gas planets the Jovian planets that is the solar system data on page 15 of the reference table now how do we know that the Earth revolves and rotates how do we know that they go in an orbit around the Sun and that they spin on its axis there are two proofs for the revolution the first is that you see different constellations uh in our night sky you see different constellations which means groups of stars so during the months of June let's say you'll see during the months of June you'll see these constellations over here but since the Earth orbits around the sun we will see different constellations so you'll see that in the questions they'll say how come we see different constellations in one month and another constellation in another it's because the Earth orbits around the Sun and Moves In A Circle not a circle a over shape around the Sun so we different see different constellations that's one proof and the second proof is the seasons which we'll get to soon and the seasons is that you have winter you have summer it's because the Earth orbits around the Sun it doesn't stay in one place so sometimes the sun's rays will hit directly at different points on earth based on where it is in its orbit around the sun which we'll see soon that is going to be a proof for the revolutions now how do we know that the Earth rotates on its axis how do we know that planets rotate on their axis so the answer is that there two proofs is going to be the focal pendulum is one proof and the second proof is called the cholis effect so firstly you have the focal pendulum the focal pendulum is you have a free swinging pendulum that is moving side to to side from the ceiling here so just moving side to side but it will knock down all the pegs in the circle the reason is is because the Earth is orbiting underneath it causing the pins to spin and therefore even though this is going back and forth Just side to side it will knock over all the pins in the circle and therefore that is a proof that the Earth must be rotating causing these these pegs to move and allowing the pendulum to hit all of them over the second proof is called the cholis effect they have winds on Earth do not move in a straight line they don't move in a straight line This is on page 14 of the reference table the winds do not move straight in the northern hemisphere they move clockwise in the southern hemisphere they move counterclockwise that's called the coris effect if you were on a Maro round and you threw a ball to someone on the other side of the Maro round the ball would curve it wouldn't go in a straight line since the Maro round is moving so we see that the the wind's curve on Earth it must mean that the Earth is rotating on its axis so those are two proof for rotation then we have Earth so we saw the the the universe the galaxies the Stars the planets and then we have our planet which we are on that is the planet called Earth now Earth is the only planet we know of that can sustain life that has life so there's different characteristics of Earth so here on page one you have the average chemical composition of Earth's crust hydrosphere and troposphere again everything in the universe is made up of at ATS of elements and these elements come together to make up different compounds so you have different parts of Earth you have the crust that is the top Solid layer of the Earth that's what we're standing on the crust the the land but also you have the the oceanic crust you have the continental crust which we got to but that you'll see its percent by mass is mostly made up of oxygen and silicon but the percent by volume it's mostly made up of oxygen as you see in this chart here the crust the hydrosphere that refers to the oceans which are 70% of Earth's surface you have to know that that 70% of earth's surface is covered in water covered in the hydrosphere that is made up of 66% hydrogen and 0 and 33% oxygen that is H2O so it's made up of water that is hydrosphere the troposphere that is the layer of gas that surrounds the earth called the atmosphere the troposphere is the first layer of the atmosphere and that is made up of mostly nitrogen which makes up 78% and oxygen which makes out about 21% of the atmosphere that is what we you know the air that we're walking in that we're breathing in now we have the seasons now what causes the seasons on Earth we experience different seasons you have the winter the summer the fall and the spring so what causes that is that the Earth the sun's rays will cause the sun's direct rays will cause the different seasons now the Earth is not straight like this the Earth is actually tilted at an angle of 235° on a line as you see here on a line that is perpendicular to the plane of the Earth's orbit so this is a line that is the plane of the Earth's orbit as it orbits around the Sun and this line right here is perpendicular it makes a 90 degree angle with that plane of the Earth's orbit and you see how this is the uh ax axial tilt see how it's tilted back 23 and half degrees to a line that is perpendicular to the plane of Earth's orbit now this tilt will cause different seasons that sometimes it'll be hot in the Southern Hemisphere and sometimes it'll be hot in the northern hemisphere there are two reasons two main reasons why a place is hot or cold on Earth one reason is the angle of insulation which means how direct the sun's rays are so for instance how direct the sun's rays are an insulation insulation means incoming solar radiation which means radiation from the Sun so there's two main ways for a place to be hot or cold the first way is the angle of insulation if a place gets direct sun rays from the Sun at 90 Dee angle that is the that is the most intense angle to get at 90 Dees that it's going to be the hottest place on Earth if it's going to be let's say a a less angle like 40 degrees or 15 degrees it won't be as hot it will be much colder that is called the angle of insulation if you have direct sun rays is going to be the hottest then compared to a place that's say in the North or South Pole which will got less direct sun rays the second way is the duration of insulation which means duration how many hours of daylight that place gets so since the Earth is tilted if you see here for instance in the southern hemisphere they're getting more duration of insulation so we'll see since the Earth stays tilted as it orbits around the Sun you will have the different seasons so first you have you have four seasons and you have 12 months so every three months is a new season so first we'll start off with the winter Solis and ironically that is when the earth is closest to the Sun actually during the winter Solis and we really refer to we really talk about the northern hemisphere what they are experiencing in the northern hemisphere so it so in the northern hemisphere we have first we have the winter Solus on about December 21st and that is the first day of winter and what happens is the sun's Rays hit directly at the 23 and a half degree south line at the 23 and a half degrees south line which is the Tropic of Capricorn and since it hits directly at this point here then the southern hemisphere will be facing towards the Sun and will be hotter the nor Northern Hemisphere where New York is located we're located in New York which is in the US in the northern hemisphere it is tilted away from the Sun so it's going to be colder since we're tilted away we get Less Direct Rays from the Sun in the southern hemisphere they get more direct Rays so it's going to be hotter but it's going to be colder for us in the northern hemisphere so for someone in New York someone in New York the sun will appear much lower in their daytime Sky see here on December 21st on December 21st the sun will appear much lower in our daytime Sky because we're were tilted away from the Sun now also we have less duration of insulation we got less hours of sunlight you can see the North Pole is completely in darkness but in the southern hemisphere they get more hours of sunlight for us in the northern hemisphere we get less hours of sunlight so for those two reasons less director raay and less duration of insulation it's going to be colder in the northern hemisphere therefore it's referred to as the winter solstice now again three months later after December 21st you then have March 21st and you have the first day of spring this is called the Spring Equinox and the sun's Rays hit directly at the equator directly at the equator and it's called The Equinox because it's equal that all places on Earth will have 12 hours of sunlight and 12 hours of Darkness it's going to be uh warmer during the Spring Equinox than it was by the winter econox for us in New York and that is because we get more direct sun rays you see how it's heading at the Equator so we're facing a little bit more towards the Sun and getting us to be warmer now during this time the Sun will rise in the due East and then set du West for us in New York and you see how it rises further up in the daytime Sky it rises up further in the daytime sky and that is called that is by the Spring Equinox now three months after the Spring Equinox three months after March 21st is going to be June 21st and that is the first day of summer for that is called the summer Solus and in during the summer Solus the first day of summer you see how the 23 and a half degree North Line the Tropic of Cancer is now facing towards the sun getting the most direct Sun Ray therefore the the northern hemisphere is facing towards the sun therefore it's going to be hotter for us in the northern hemisphere it'll be colder for those in the southern hemisphere but it's going to be hotter for us in the northern hemisphere because we get more direct sun rays and we have more duration of insulation you can see how more of the sunlight we're getting more hours of sunlight during that time because we're facing towards the sun that's called the summer Solis and since we're facing towards the sun the sun will rise much higher in our daytime sky will rise north of due east and set north of Due West it's going to it's going to go much higher in our daytime sky during the summer soltius now three months after that you have the September 21st and on September 21st you have another Equinox that's called the Fall Equinox and that is when the Suns rays will hit directly at the equator as well again by the equinoxes the Suns Rays hit directly at the equator and when it hits it at the Equator we will have it's called The Equinox because we have 12 hours of sunlight and 12 hours of Darkness so you see for someone in New York you see how the sun rises to East and sets to West during that time that is by the Fall Equinox so again you have the Four Seasons the winter Solus were facing away from the Sun therefore it's going to be less direct rays and less hours of sunlight so it's going to be colder and then you have three months later the March 21st the first day of spring it hits directly at the equator then you have the summer Solus it hits directly at the 23 and a half degree North line so it's going to be hotter for us in the Northern Hemisphere and then you have the Autumn Equinox 3 month after that September 21st where it hits again at the equator directly causing the equator to be the hottest and having 12 hours of daylight and 12 hours of Darkness for all places on Earth so those are the four seasons and a proof for the Earth revolving around the Sun hi I'm Donnie rudenski from Regents made simpler and you can purchase this entire course for only $89 this includes a two-part review of all the material you have to know in a simplified version plus video review with visuals of the past of the past two regent exams I am putting up one for the third as well for June 2023 as well so you can get that all for $89 which is actually less than a typical one session with a tutor a personal tutor which usually you will need a few sessions of but you can watch this this course at your own pace for only $89 and know everything you need to know for the upcoming exam in just three hours without using any flash cards anything like that using this course that's on the bottom right here clicking there to go to Regents made simpler.com you can see this course here I can show you a little bit of it so here we have biology and earth science as well and what you'll get again is a two-part review review course going over all the material you have to know in a simplified version and as you see version plus video review of Vis and visuals with visuals of the past region exam so here you could see here it's not just a video of me explaining the material it's also me with visuals from the reviews going over that the questions as well and go going over why the answers were wrong as well so be sure to check that out here on the bottom clicking here to go to Regents made simpler.com